Two and a Half Men: Ashton?!

I just read that Ashton Kutcher is "replacing" Charlie Sheen on "Two and a Half Men"... This is all fine and dandy, I understand their desire to keep the show up and running, but really? Okay, a few questions: can a show be the same when the star is taken off? Disregard his "real life" character, that he may be a little crazy, etc... Must the show go on, when the main star is no longer able to be played by the same actor? Second question, and most important really - Has there been any mention or speculation as to whether or not Ashton is meant to play the same character that Sheen played? I mean, it's one thing to replace an actor with another because you have to have character balance, but unless you're making "Batman" sequels, you can't exactly change around the actor who plays the star role...

So the big question is: Is Ashton playing Charlie, or is he playing another, brand-spanking-new, character to replace Charlie entirely? If you have any insight or have seen an article that gives some, please do share! What are your thoughts on the show? Should it continue? Do you think Ashton was the right replacement?