If you make plans for a big event on the 29th, t1mmy & I will probably be at SCC. Maybe you can make it a smaller event to get your roommate used to people playing a game for hours at a time first.
I think people didn't think Ice Climbers wouldn't make it back because they caused a lot of problems for programmers in Melee. But with the huge staff working so long on Brawl it's not a surprise they had time to include them (as well as loads of extra bonus feature, including wifi).
Speaking of wifi... yeah, it's going to lag terribly when you first play it. I am saying this because it will have a large amount of traffic in the first few days when everyone tries out the wifi feature. This happened with Mariokart for the DS. That game was insanely popular for a wifi title (more people were playing Mariokart DS online in just the few days it was released then Halo had).
And, yeah, Halo 3 is obviously going to cut into some peoples' Brawl playing time, but so is ping pong, movies, school, work, etc. After Halo 3's hype cools down people will still be playing Brawl, I mean, nobody really thinks Halo 2 affects Melee's crowd.