As this SF Chron article illustrates, Americans, with generally diverse backgrounds, root for diverse teams. It's not that we don't love Team USA - but, historically, our men's team didn't always make it to the big games (or the little ones I guess).
So we have alternative favorites. I like to think it's a way to connect with the world. Growing up with an Italian grandmother, Italy was always a household favorite. In the past, I've flirted with Russia and of course supported my best friend's beloved Croatian team (my best friend's and half my hometown's favorite, that is). Now, England will certainly be on my watch-list as the games heat up.
In 1994, I watched practically every game broadcast since they were held in the US and I was laid up on the couch recovering from knee surgery. And I saw the American women beat China at the Rose Bowl in 2000 - that was a game.
Check out the FIFA World Cup site here - or go straight to the groups and standings here. Geography not so hot? There's a map too.
Teams on my watchlist: USA, Italy, Croatia, England, and perhaps Switzerland because I had such a great time there, and maybe Iran - just for kicks.