I think the problem is that OCUK is a family friendly forum and for the most part, while playing games people arent family friendly so it would cause issues on teamspeak from those wanting an innocent game compared to those who communicate in swearies all the time. That alone would cause people to grief each other "telling on people" ect. People likes to troll.
I play in a few different groups here for various games and even various groups within those games. I'm a bit promiscuous like that you see but each group has their own teamspeak which is usually related to their clan or group, teamspeaks are relatively cheap and when a group involved its literally pennies a week to host one.
Smaller groups of people say 2-4 probably just use Skype and have a group chat on whatsapp/steam to organize playing together.
The hardest part would be heading a community with a leader everyone is happy to let mediate any problems, then you'd need to find someone who wants to deal with that anyway and you'd again get people separating away from this as they dont like how its being run. It is often easier to have your own admin rights on a server but thats easily done with a passworded channel on a teamspeak with someone having channel admin thats trust worthy for that channel, just again you need to be able to trust the owner of that server.
On this note, I'm happy for anyone to use our teamspeak, create yourself a channel and get an admin to permanent it if you want or just keep making it when you join the server, we have plenty of slots. If for some reason they all fill up, I'll look at increasing the amount but I don't see that happening anytime soon.
As for an actual OCUK community, I think most would agree here, at least for Arma related servers and similar types of games that MarkeR is the man for this. I think Linktart (apologies if this name is wrong) runs a Minecraft server? I don't know of anymore ocuk related community servers as everything else I play has its own servers or at least I dont have any regular servers I know of
Maybe its worth starting a post with links to communities and their respective games they host/support? Not sure if thats allowed through OCUK though.
Teampeak Details: 188.165.222.198:9987 - No password.
Edit: Heh I thought it was Frenchtart but I only glanced at your sig.