Re: Guy Pearce is Aldrich Killian
There's an old saying in Marvel comics: Nobody ever stays dead in the Marvel Universe, except Uncle Ben. The "resurrection" of Agent Coulson in the upcoming "Agents of SHIELD" TV series is proof of that.
It just comes down to whether or not the studio feels like they could get more mileage out of the character. If they do feel that way, then it'd be simple enough to say that Extremis-enhanced Killian is basically immortal, and survived the blast from Pepper.
The only way I'd really see him coming back, though, is if they choose to put together a "Masters of Evil" supervillain team for, say, Avengers 2, as a lot of posters here seem to hope.
THE COTTON AVENGERS
...They move like slick cotton on oil.