From June 19th, the Game Zone will no longer support any cd games. The chat lobbies will disappear and games will be arranged through M$N Messenger.
Needless to say, this will end the postponed death sentence of CFS1 as well.

http://zone.msn.com/en/general/article/genbeyondthezone.htm

There are other threads about that.
Some have gone to Gamespy and Hyperlobby, though I find there's too much spyware on Gamespy and there's almost no community on Hyperlobby.
Some squads have set up their own servers.

I don't have any more than have been posted already, and then only to help the folks who wanted to carry on with it.
The few I have visited all seem to be of the 'pay-to-play' variety which tends to adversely affect my Scottish gene.
Personally 50% of the reason I stuck with CFS1 was for the fun CFS1 community in the Zone and, because of that, I don't intend continuing somewhere else when the Zone boots it.
I accept that there is a new community starting to spring up but I can't see it developing into anything worthwhile anywhere else now.