Honestly, my group uses Discord (http://discordapp.com) now. We love it. It replaces IRC and Teamspeak for us. Plus, I can get a user on the service in 5 seconds just by sending a link to them.

It is mostly used for gaming, but coding with it is just as great. There are a lot of public servers also for all sorts of things. (http://discord.me/servers).

The voice is what we love it for, chat is awesome during the day when some of us are not able to talk over voice.