With the addition of two new teams, the Portland Timbers and Vancouver Whitecaps FC, MLS has realigned for the 2011 season. Houston Dynamo will be moving to the Eastern Conference to balance the league with two nine-team conferences.
As the eastern-most team in the West, it was perhaps a forgone conclusion that Houston would move to the East. The move, however, isn't a great one for FCD fans. The club's three previous rivals, Kansas City (The Ron Newman years), Chicago Fire (The Brimstone Cup), and now in-state rival Houston Dynamo, are all in the Eastern Conference.
That leaves only playoff nemesis Colorado Rapids and the "FCD North" Real Salt Lake as potential in conference grudge matches, although LA Galaxy games have certainly had some extra weight since the Landon Donovan throat slash.
Here's the new conference alignment.