I work at GXC, I just wanted to post with this profile so I could be clear when I'm not officially speaking for the store.
It's been my impression that SC4 has been on the decline, and I don't know much about Tekken's following. I would love to do a BlazBlue tournament, but we're kind of worried about the turnout...at least for our early tournaments. While we're getting our tournaments up and running we need to focus on games with more appeal to the general public. Once they're a bit more established, we'll try and and run some more fun ones.
I made this post to see if I was missing any mass appeal games (like Gears...thanks for that), and also to get some ideas for later tournaments. So, we might try for some BlazBlue, older Street Fighters, maybe some racing, or who knows what else, but those may take a while for us to get to.
I'm going to see if we can do a Gears 2 one in Feb or March, before Gears 3 hits in April.