I was looking around Steam a few weeks ago, trying to troubleshoot a little quirk. Anyway, I came across a suggestion that all Windows Vista users should switch to the Steam Community Beta version since it runs many of the functions as a Service in order to work better with Vista. Anyway, I downloaded it, and it's pretty sweet. On the surface, it looks pretty similar. Basically, what they have done is implement the functionality of Xfire, Facebook, and Ventrilo all into Steam (as well as all the stuff that steam used to have). With steam finally boasting hundreds of games, friends support in all games (via overlays), statistics tracking, profiles, avatars, facebook-esque groups, and voice chat (1 to 1 or group chat), its looking to be pretty solid. It supposedly also supports playtime stats + chat overlay for games that aren't even on steam, although I haven't messed with this feature yet. Of course, it's buggy as it is a beta. The most major is that the voice chat seems to just entirely not work for certain users. I've had it work with 2 of my friends but the rest of the time it's a no go. Furthermore, it is a "phone call" style voice chat rather than a "radio" style. Having a push-to-talk option would be better for gaming imho! Another issue is that the chat overlay process doesn't follow properly for games that use a launcher... probably because it is set to overlay the launcher application which is closed as soon as you choose to load the game. The facebook-style groups are pretty nice, basically gives you a free site & voice chat room (not sure on size limit for this chat) that is easy to set up. I could see this getting popular for people who run small gaming clans/guilds. Of course, the downside to all this free voicechat is undoubtedly a huge rise in Ghosting+Voice Chat cheesiness in CS:S
