Scott Feinberg has a good piece up about why Little Miss Sunshine will win the Oscar. I'm not as convinced but it is my current guess as well and was before reading this. I just think it has the virtue of being a standout in the lineup. Not the best mind you -- My vote would go to The Departed -- but the standout. It has a feel good warmth that alludes the others and the other films seem more easily narrowed down to a particular strong element rather than a 'whole' package. The Queen is The Mirren Show. Babel is all about its multi-continent message and sprawl. The Departed is Scorsese doing his crime thing to great popcorn effect. But Little Miss Sunshine? It's a whole package. How do you separate its elements?
In truth either The Departed or Little Miss Sunshine as a winner would be delightful because it would be Oscar finally trying something different. Honoring a pulpy crime flick or a straight up goofy comedy? Unthinkable. Which is exactly why they should think seriously about doing it. I've updated the Best Picture page with detailed comments and the current prediction.