While the pre-credits were a bit strenuous on the eyes, I genuinely enjoyed everything about this movie. The scene cuts were fantastically done, as can only be expected of Hot Fuzz director Edgar Wright (seriously, go watch that movie, the cinematography is superb).
I felt that the emotion shown, while perhaps not up to the standards of "mainstream" rom-coms, was more what one would actually see in a modern-day relationship such as this. I actually liked the nonsensical and seemingly-unjustified mood swings, because that's how a majority of twenty-somethings function!
I almost had a nerd-gasm right at the beginning, during the Universal logo scene (if you've seen the movie, you'll know what I mean), and the graphic elements made everything pop with the perfect amount of movie+comic-book mixture.
All in all, I think my VERY favorite 'omg, that's awesome' moments came near the end, and is what MovieBob references in this article (MAJOR SPOILERS)
When Scott Pilgrim gets his second life, not only does he go through practically the same scene as before, rectifying any moral slip-ups(just like gamers often do), he ALSO chose to skip through a majority of the dialogue and mooks because he'd done it all before, and wanted to get to the big bad. To gamers EVERYWHERE, that should be such a colossal sign of game-to-movie transferal, as it is common practice to mow down minor baddies and hold the 'next' button through repeated dialogue just to get to the fighting and major decisions! Maybe it's not as major as I'm making it out to be, but it was a wonderful nod to the videogaming generation that inspired so much of the movie.