Like Shin, I have come to stop dating girls whose musical taste clashes too much with mine. It really, really doesn't work.
Other than that, I can get
anyone to enjoy a video game. I got my mother addicted to Pikmin 2, and my dad is a huge fan of Yoshi Touch & Go. My last ex-girlfriend (who
hated games when I started dating her) is currently an avid World of Warcraft player, and I play Puzzle Pirates with my current girl.
So no, it's not a prerequisite trait, because they'll end up gamers if they spend more than a day with me anyway. =D
As for the whole "attractiveness is important", of course that's true. But, I think it's more important to guys than to girls. Admit it lads, you don't want to be dating some ugly broad, no matter how open-minded you are.
My experience is girls go more for the "charm" factor: ie. smooth talking, cocky/confident, sense of humour...
(I suppose that if you define attractiveness as "the traits that make a person attractive", then charm and even personality rank among them too, but you know what I mean.)
EDIT: I like your av/sig, Hydelloon.
Jam it back in, in the dark.