OK, now that we know what we're talking about, let's not waste any time.
I think we're all in agreement that that trailer was excellent. So let me dig in a bit deeper into what I took away from it.
The Mandarin
So I'm not 100% sold on Ben Kingsley as the Mandarin, at least not yet. There's too much unknown. I will say that his one voice-over line is very cool. I do like that he actually has ten rings (at least in that one shot), though I'm not sure if they plan to go all-out and make him a fucking techno-sorcerer. My biggest concern is that they make him too conventional. At SDCC in July, Shane Black confirmed that he would be called "the Mandarin", and I'm also curious on how they managed that considering how much support this film has been getting from Chinese investors. They might do what they did in the other "Iron Man" films and just call the bad guys by their real names, but the Mandarin has always been larger-than-life. I guess we'll see.
In any case, what I AM happy about is that it appears that for once, an Iron Man villain is taking the initiative and going on the offensive at the end of the First Act, rather than save the big confrontation for the Third Act. Whiplash SORT of went on the offensive in "Iron Man 2", but his attack didn't up the stakes like it should have. It didn't really affect Tony in any way other than give him some negative press, which didn't really matter all that much to him. None of the villains in the earlier Iron Man films were actually antagonists in the Hollywood Formula sense. They didn't really do anything to impede Tony Stark's goal. In the first movie he just wanted to find an outlet for his guilt and new-found sense of responsibility. All Iron Monger did was give him a Third Act climax. In the second movie, Tony needed to find a replacement for Palladium and learn to stop putting all of the weight of the world on his shoulders. That's one reason why "Iron Man 2" isn't a tight film in terms of its narrative... most of what happens has nothing to do with the central conflict.
In this film, it appears that the Mandarin will be directly attacking Tony Stark and forcing him into desperation, which makes for a much more interesting drama. The Mandarin is actually acting as an antagonist by presenting the core conflict and acting as the primary obstacle in that conflict.
Tony's Self-Assembling Armor
This has been talked about before, but now we finally see what it is leading to. Since the first film, Tony has been finding better and better ways to put the suit on. In the first film it was a whole process. In the second film, he could put it on with a suitcase. In Avengers he had a walking disassembly track and a mobile coffin-shaped suit that he could put on in mid-air.
In one shot, we see a part of the armor fly across the room and attach itself to Tony.
Anyone who has read the "Extremis" storyline will find this relatively familiar. When Tony injects himself with Extremis, he basically becomes able to telepathically move his suit. This doesn't just help him with the assembly process, it also makes him faster and more powerful. It also allows him to telepathically communicate with satellites and such as well, but let's not get too into it.
Still, I don't think we're dealing with Extremis here. At least not necessarily in this shot, and also possibly not to the extent we had it in the comics. In the comics, Extremis is a big deal and it nearly kills Tony. I don't think he would get access to Extremis in the First Act of the film, as it seems to imply here.
Also, in later scenes, we see the armor fully assembled without Tony inside it, attacking him and such.
There's a few ways this could be happening.
1) Tony has built in a sort of auto-pilot AI into the armor so that it can respond more quickly and not rely on his own reaction time. It also makes it so it can automatically assemble piece by piece anywhere at any time. Then it becomes self-aware and tries to fight him. For extra fun, what if the AI was Jarvis?
2) Tony just created some form of remote control over the armor and then it gets hacked into by the Mandarin or somebody, perhaps to kill him and/or steal the suit. He then has to use Extremis towards the end of the film to regain control of the suit.
3) Tony IS using Extremis and the armor is attacking him because he still hates himself for any number of valid reasons.
4) It's just a dream, in which case, that's such bullshit.
Pepper
Gwyneth Paltrow has gone on the record saying that she doesn't know if she'll continue to keep coming back as Pepper Potts. That of course leaves us with a very important question... are they going to fridge her?
One reason why audiences were so taken with "Iron Man" was because of the unconventional ending where the hero decides to chuck the secret identity out the window. However, we tend to forget that heroes generally do that for a reason.
But it's important to remember that so far in the Marvel Cinematic Universe, none of the heroes have had "secret identities". It's no secret who Iron Man, Hulk, and Captain America are, and the only time they pretended Thor was anyone other than Thor was when they were sweet-talking Coulson into letting him go.
I don't think anyone realizes that secret identities really aren't a thing in this universe. At least... not yet.
It's pretty clear in this trailer that Tony is at the very least incredibly concerned for Pepper's safety and that Pepper will, in all likelihood, face some serious danger (she usually does).
So will they kill her off? It does make sense, particularly if Gwyneth is serious about ending her work in superhero films.
But personally, I don't think they'll actually KILL her. Marvel is aware of how big its female fanbase is (particularly when compared to their comic book fanbase) and they probably know full well that killing her would piss off a LOT of fans and infuriate a LOT of feminists. Also, if you're familiar with the recent comic book canon, you'd know that Pepper was mortally wounded and then rebuilt a la "Six Million Dollar Man" into the superheroine Rescue. It is important to note that another character in this film, Eric Savin, is also a cyborg (at least in the comics). It would not be a stretch if Pepper is severely wounded, even presumed dead, and then comes back thanks to previously-established cyborg stuff courtesy of Savin.
Either way, something serious will probably happen to Pepper and it will probably make any future superheroes think twice about going public in the same way Tony Stark did.
Iron Patriot
We don't see much in the way of Rhodes as War Machine/Iron Patriot. I do agree with the consensus that re-imagining Iron Patriot in this way is inspired. In the light of what happened in New York, it wouldn't be surprising if the U.S. Military-owned Iron Man suit would be rebranded as a hybrid between Iron Man and Captain America. I think it's great, though that kind of raises more questions than it answers.
What Haven't We Seen and How Does It All Add Up?
There have been a lot of hints and rumors floating around during the filming and not everything has been revealed in this trailer. The previously mentioned Eric Savin has yet to make an appearance, we catch glimpses of Aldrich Killian and Maya Hansen (the creators of Extremis), we haven't seen A.I.M., we haven't seen Firepower...
That's a lot of stuff that we haven't seen, and I'm having a hard time imagining how it all pulls together, but here's what I'm thinking.
After what happened in New York, the whole world has collectively freaked out (think the end of "Watchmen"... the comic, not the movie). They decide to have some kind of scientific summit to discuss how to advance their technology so that mankind is better prepared in the event of another alien invasion. That would explain the presence of pretty much every character I mention above.
Of course, that doesn't really answer the question, "What does that have to do with Tony Stark's battle with the Mandarin?"
I don't honestly know, but here's my crazy idea.
Let's assume for the moment that the Mandarin is going to be as crazy-powerful as he is in the comics. Effectively an all-powerful techno-sorcerer with nigh-unlimited resources and an extremely powerful intellect.
Based on what we currently know, this is how I think the plot will shake out:
Act One: Tony and the world are still reeling from the Battle of New York. Tony is working on making his armor remote-controlled or whatever and there's a big world summit for weapons manufacturers. Rhodey tries to convince him to go, but he declines, stating that he doesn't make weapons anymore and Rhodey calls him selfish for keeping this technology for himself. At the summit, the various world powers, predominantly the U.S., China, and A.I.M., will present Iron Patriot, Coldblood, Firepower, and Radioactive Man as their answer to the Avengers in order to keep the world safe from future alien invasions. Then, the Mandarin shows up and schools them all. Meanwhile, Tony's suit goes rogue and as he fights it off. Eventually he disables it. He creates a new suit that is less volatile, but then it is stolen when the Mandarin hacks into it and gets it to leave Tony's place before the Mandarin sends helicopters to blow up the building, making sure that Tony can't come to stop him at the summit. With no other option, Tony suits up with the malfunctioning AI suit and barely manages to face off with the Mandarin, but since his suit is not cooperating, he loses and gets left for dead somewhere in the frozen tundra. Having sufficiently proven his might and technological superiority, the Mandarin states that he is the only one capable of protecting the world from another alien attack and that if they want his help, they must make him supreme ruler of the world or something.
Act Two: Tony's colleagues and allies are wounded and worlds away. He has no home, no resources, and he's on the run. Pepper is probably in some kind of danger (let's say kidnapped). All of Tony's armor has been destroyed except for the suit that the Mandarin stole. The Mandarin, with A.I.M.'s assistance, starts mass-producing the armor. Meanwhile, Tony tries to repair the malfunctioning suit but still has no way to properly control it. He finds out about Extremis somehow and meets up with Killian and Hansen (or he already has Extremis somehow and begins to mess with it). The Mandarin finds out he's alive, but then kills Pepper to make Tony hit rock bottom. In desperation, Tony uses Extremis, which eventually works like in the comics. He then fixes up his suit. Meanwhile, Eric Savin saves Pepper, but it's left ambiguous as to what it means.
Act Three: Tony faces off against the Mandarin, but it's a tough battle. Eventually Iron Patriot shows up to help out. Then Rescue shows up and at first we aren't sure who it is, but it is quickly revealed to be Pepper, alive and well. They still aren't enough to take down the Mandarin until Tony uses Extremis to take control of the mass-produced Iron Man suits to act as his personal army. He ultimately wins, but the Mandarin lives to fight another day. Using Extremis to remote-control the armor, Tony makes it appear that he is retired as Iron Man since he does not want to put his loved ones in harm's way. Then we get some other thing that will lead into the next Marvel movie.
So that's my current guess. It's likely to change, but I do love my speculation.
Wrap It Up
So yeah, awesome first trailer. Can't wait for April.