It's really all about George
CNN.com has an interview with George Lucas where he responds to the criticism he has received for not releasing the original Trilogy and opting for the special editions instead. IMO, he comes off like kind of turd (as usual):

Q: Why not release both the originals and special editions on DVD?

LUCAS: The special edition, that's the one I wanted out there. The other movie, it's on VHS, if anybody wants it. ...

I'm not going to spend the, we're talking millions of dollars here, the money and the time to refurbish that, because to me, it doesn't really exist anymore. It's like this is the movie I wanted it to be, and I'm sorry you saw half a completed film and fell in love with it. But I want it to be the way I want it to be

Q: Do you pay much attention to fan reactions to your choices?

LUCAS: Not really. The movies are what the movies are. ... The thing about science-fiction fans and "Star Wars" fans is they're very independent-thinking people. They all think outside the box, but they all have very strong ideas about what should happen, and they think it should be their way. Which is fine, except I'm making the movies, so I should have it my way.

Too bad he didn't rethink all of the damn Ewoks he had running around in "Return of the Jedi." I'll only concede that reworking the original films is warranted if he is able to replace Anakin when they release the prequel DVD set.