There's the scene where one of his suits wakes up Pepper Potts while Stark is in bed with her (or that's Iron Patriot but it's most likely an out of control suit). Another scene is when Stark is on the ground and one of his suits is right on top of him (above screenshot). The most important scene in the trailer could be on Air Force One.
If you go frame-by-frame (you don't have to since we have two screenshots from this scene below) you'll see an Iron Man suit hand come through the plane, which causes the explosion and sucks people out of the plane and into the sky. See for yourself...
So what might be one of the biggest questions, followed by one of the biggest speculations, is to ask, "Is Stark losing control of his suits or are his suits 'coming alive' on their own?"
Using the nanotech virus, Extremis, from the comic book universe maybe the Mandarin has found a way to use Extremis to control Stark's suits. Or maybe someone else is in the suit altogether.
But in a bit of big-time speculation, let's say Stark is on the brink of creating Artificial Intelligence and what we are seeing is his suit(s) realizing this on their own. If A.I. is being introduced then that means Extremis is setting up the possible introduction of Marvel's greatest A.I. robotic villain of all, Ultron. But of course that would mean Marvel's Ant-Man movie is being set up by Iron Man 3 as well—and this isn't the first time we here at The Daily SuperHero have speculated this idea either.
It's all guesses right now but why not have fun with it at the same time, right?!
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Iron Man 3 trailer observations and questions with screenshots
Iron Man 3 is looking like it has a ton of influence on setting up Marvel Studios' Ant-Man movie