Seattle - because of their lively play, Drew Carey, atmosphere, colors and X-Box insignia.
Portland - because of their stadium and environment; the soccer equivalent of Wrigley or Fenway.
Kansas City - because of Zusi, Feilhaber, Kamara, their stadium (one of the best), their style of play, and this:
LA Galaxy - the MLS equivalent of Man United, I still like them for their colors, kit, Beckham, Donovan, and Magee.
Chivas USA - they can frick off and die.
Pretty much how I feel about things, with an added attachment to Houston since it's the closest team to BR, I have family there, and I've been to a few matches.