Why He Could Do It: In many ways, Steve Carell is something of a successor to Hanks; making his name with comedy before showing his range with straighter roles. The actor has been good value in some of his presenting appearances so far, and is generally beloved in Hollywood. Plus, as a veteran of Second City, he has plenty of experience with a live show like this.
Why He Might Not: Carell is at a bit of a crossroads of his career: some of his recent films ("Dinner For Schmucks," "Seeking a Friend at the End of the World") underperformed, and he's still looking to cement his movie career after exiting "The Office." He's also got a big year coming up in 2013 with a "Despicable Me" sequel, "The Incredible Burt Wonderstone," "Anchorman 2" and Bennett Miller's "Foxcatcher" -- the filming of the latter two could well be a scheduling problem -- so he may not have the calendar space available. Furthermore, his comic persona is a little more off-kilter than someone like Hanks -- would a ceremony hosted by Carell end up feeling like the Dundies?
Why He Could Do It: The king of the comeback, Robert Downey Jr. has become, in the last few years, one of the most popular movie stars on the planet. After "The Avengers," he's bigger than ever, and a Downey Jr.-hosted show would be sure to bring in a younger audience. He's been behind some of the highlights of ceremonies in recent years (particularly his double-act with Tina Fey), and in theory, should be able to joke it up, and yet bring some gravitas in for the serious moments. Right now, he's got nothing firm on the calendar after "Iron Man 3" so he might have some time.
Why He Might Not: RDJ's persona has come closer and closer to Tony Stark's in recent years, and his bit with Gwyneth Paltrow last year was more smug than entertaining. Does he really have the right kind of warm and fuzzy feel for the Academy? He's not exactly Billy Crystal.
Why He Could Do It: It's clear from the Jimmy Fallon talks that the Academy isn't necessarily leaning towards movie stars, and if they go into the late night world, they're unlikely to go with David Letterman again, Jay Leno seems too milquetoast even for the Academy, and Jimmy Kimmel (the natural choice, given that he's on ABC) has been ruled out because he's hosting the Emmys this September. As such, the obvious candidate would seem to be Craig Ferguson. In many ways, the Scottish actor/comedian is a better fit than his late night rivals: he's a well established actor (most recently voicing a part in "Brave"), he's able to turn on a sixpence from gags to more serious moments, and he's got both an old school chance and a younger following.
Why He Might Not: If ABC weren't willing to let Fallon, who hosts a rival show on NBC, host the awards, we can't see why they'd change their minds for Ferguson, so the chances of this happening are very slim. Maybe the Disney connection through "Brave" would warm them up to the idea, but it still feels unlikely to happen (and the same goes for Conan O'Brien, for that matter).
Why She Could Do It: Adams has quietly become not just an Academy favorite (three nominations in seven years), but also something of an A-list star, leading big hits as diverse as "Enchanted," "Julie & Julia" and "The Fighter." She's got comic skills, can pull off a bit of a song and dance (her performance from "Enchanted" a few years back was a charmer), but could handle the more somber moments too.
Why She Might Not: Adams looks like a serious Supporting Actress contender for "The Master," and might well figure into the race for "Trouble with the Curve" as well, so there'd be a bit of a conflict there. Furthermore, there's not much precedent for an actress hosting solo; they've either been part of a double act, like Anne Hathaway, or an established comic presence like Whoopi Goldberg or Ellen DeGeneres. Co-hosting with someone like Jason Segel might ease the minds of ABC suits, but he's likely to be tied up on "How I Met Your Mother." Plus, Adams may be filming David O. Russell's latest film in the spring, which would count her out.