This may sound absolutely stupid, but think about it for a moment.
The Academy has honored very few science fiction or fantasy movies with anything other than technical Oscars. Lord of the Rings: The Return of the King is the only one to actually win one. (Even Star Wars lost to Annie Hall. Annie Hall is a great movie, but Star Wars is better, and more enduring.)
Movies based on comics get routinely screwed. How many have been nominated for serious Oscars? I don't think any. Films like X-Men, Spider-Man 2, or Batman Begins deserve more credit than they get. Hell, Michael Caine should've just been handed an Oscar for his performance as Alfred Pennyworth.
TMNT didn't even get nominated this year for Best Animated Feature, despite it having the best animation yet seen in a CG cartoon, hands down.
Oddly, The Incredibles, a film that looks like it was based on a comic but isn't, won Best Animated Feature. But, well, one would have to be a total blithering idiot to even assert that any better cartoon came out that year.
Tim Burton gets routinely passed over. I'm not saying every movie he makes is great (though I like them all). But why are movies like Ed Wood, Edward Scissorhands, and especially Big Fish never included in the running?
Corpse Bride lost Best Animated Feature to Wallace and Grommit: The Curse of the Were-Rabbit. Not that W&G was a bad movie, but it wasn't especially great, either.
Speaking of which, why has Danny Elfman been equally screwed? He's been nominated for only three scores (Big Fish, Men in Black, and Good Will Hunting), none of which were his best work. And, between The Nightmare Before Christmas and Corpse Bride, not a single nomination for Best Song. (If you sat through the grueling torture of the three pizza sheets from Enchanted during last night's Oscars, it becomes even more obvious that someone doesn't like him.)
And, hell, just give Jonny Depp the damned statue already! He may pick quirky roles, but he brings them to life in ways that no one else can. (I don't think it's too far-fetched to make the claim he's the best actor of his generation.)
Like I said, I'm not about to make the claim that every sci-fi movie, comic adaptation, or Burton flick should sweep the Oscars, or even necessarily get a nomination.
But there does seem to be some major prejudice against "geek movies" among the voters of the Academy, and sometimes it looks like worthy movies aren't even considered.