First of all, the site is reporting that Guy Pearce's character Aldrich Killian, known to comic book fans as the man behind the Extremis experiments, will still have a similar but somewhat limited role in the film, tying into reports yesterday that Pearce had characterized his role as little more than a cameo. Killian, then, will likely be answering to Ben Kingsley's character, The Mandarin, who appears to be pulling the strings on all of the many villains who have been teased for the film so far.
Of course, just being a villain doesn't mean you'll get tights and stuff, either. CSIcon is hearing that Chen Lu, the villain played by Want Xueqi in the film, will likely not take on the green skin and name of "Radioactive Man," as his character has in the comics. That makes sense not only because the Iron Man films tend to keep to a somewhat more realistic take on superhero storytelling but also because it saves Marvel from hundreds of jokes about their villain being a fictional superhero in the universe of The Simpsons. They compare it to Selina Kyle in The Dark Knight Rises: just because you're serving that purpose in-story doesn't inherentlyi mean you're likely to put on a silly suit and call yourself by that name.
They've also got the nicely non-specific rumor that Gwyneth Paltrow's Pepper Potts will have a lot of twists, turns and surprise this time out. They imagine she'll become more involved in the day-to-day crimefighting aspect of her boyfriend's life. That's not surprising, given the proliferation of rumors that she might suit up in Rescue armor in the film, along with the fact that Iron Man star Robert Downey, Jr. insisted Paltrow appear alongside him in The Avengers, making her virtually the only supporting character in the entire wider Marvel cinematic universe to do so.