In real life, it would be impossible to replace Robert Downey Jr. with Will Ferrell. Tropic Thunder clowning aside, the two actors are so fundamentally different in their acting styles, their intensity, their basic goals as performers, that it's impossible to imagine Downey in Stranger than Fiction, or Ferrell in The Soloist.

So why could this switcheroo work in animation? My bet is it won't. Ferrell will be replacing Downey Jr. as the lead role in Oobermind, voicing a supervillain who defeats his archenemy (newly added Brad Pitt) and finds himself bored. He then creates a new superhero (Jonah Hill, also new to the cast) who subsequently decides he'd rather be a villain too.

Tina Fey, who has been signed on since the beginning, will voice a reporter keeping track of all these heroes and villains, according to Variety. I like Will Ferrell probably more than most people, but I'm kind of bummed that we'll be getting his supervillain rather than Robert Downey Jr.'s. I can pretty much imagine right now what that guy will sound like; Downey Jr. would have been much more of a surprise.