I didn't realised so many people disliked Portal 2 until this bracket. I was one of those staunch opponents who thought Portal didn't need a sequel but the game really surprised me and I enjoyed it as much as the original. Portal was short enough that if you didn't like the humour you could ignore it and have a fun time with the puzzles. With Portal 2 being much longer I can imagine that if you don't like the writing then it would be grating to get through the whole game. The real outstanding part of Portal 2 is the co-op which I had a blast playing through. Trying to coordinate your way through all the the test chambers with another person can be infuriating at times but when you both manage to figure out what to do it's one those amazing gaming moments that you always remember.
I voted aye and said as much in the main thread for the GotG voting. Of course it's ridiculous to put Super Mario Galaxy against Rock Band but part of the fun of it is seeing these two completely different games and figuring out which one gets your vote. The main point of the bracket was to see why people voted for a game more so than what they voted for. You can always make your blog post with your personal top 10 if you absolutely disagree with all the choices that have been made so far.
It's also ridiculous because Spelunky got knocked out in the first round. Shame on you Giant Bomb community for making such a horrible decision.