SciFi could win best special effects and music, but honestly, I have not seen a SciFi that I would consider "best" picture. But then best is very subjective.
Far too many times, in my opinion, SciFi is mostly special effects and with the advent of CGI, even more so.
Take a SciFi movie and take away all the special effects. If you still have a good movie, then I think it would win "best" picture. But frankly, from what I have seen in the past, many (not all) SciFi movies would fall apart without the special effects/cgi.
As for Inception? I think my record is 20 minutes before I walk out of the room. But then, realize that I am the only human on this planet that did not like the Matrix.
