Well you switch off from being survivors and infected so yeah I was on both teams lol. Im better as a survivor though, I dont really like playing as infected.
I just came back from it a while ago and I just finished the L4D get-together thing. It was fun. I played about two matches, one on Blood Harvest (won that one) and one on Death Toll (appanrently lost that one because it disconnected all of us to the lobby screen after the other team won the finale)