Scott Pilgrim vs. the World

The other three I have no real quips about. One is a cop comedy, which they seem to be remaking now more than ever(perhaps the producer has watched too much Lethal Weapon), another is a movie about an investigator that goes into other people's dreams, and the other one is a teen-romance-comedy with outlandish movie effects and fist-fights. All in all Scott Pilgram is the most original and should be in top spot if you think about the competition.

But hey, you can't beat explosions and middle-aged women finding themselves =D

I would not have ever expected Scott Pilgrim to top the box office. It's very much oriented to a niche audience. It's for us young folks that've grown up on video games and comics and all things nerd. "Original" is hard to turn into a box office titan. Hollywood likes the familiar and accesible because the general consumer likes the familiar and acccesible. They want to know that they're likely to enjoy whatever the movie is before they buy that ticket. This is why Hollywood loves a franchise or a familar actor or director or well-read source material. Original movies that don't have a marketing juggernaut, technical gimmick, or strong cast/director generally need a big boost from winning Oscars or other awards, or somehow achieving cult status down the line.