It wasn't working yesterday for NationWar, and whenever i join a group it says "Connecting to guild voice chat" then "Voice chat disconnected"

Is this system-wide or just me?

Cool now you can hear everyone on the Guild Voice Chat channel! :D

It appears that all guilds and groups are connecting to the same TS channel, or something.

Yep. VC has done some odd things in the past, but as slime observes it now seems that it has gone universal.