I'm a big fan of the MLS (that's football/soccer in America and Canada). It probably weird for me as a Brit to be interested in it since we have such a successful football league of our own (hence why I see it as a confession), but its great too see soccer's popularity grow in the States and the players and teams get better.
In getting into the MLS I've attached myself to the team New England Revolution. I kinda got into them after playing as them on FIFA. They're certainly not one the best teams, in fact they're on of the worst, but ah well.
As a side not I ordered their kit and it arrived today!