As promised, we are slowly rolling out the third place across our network... even for ewoks!
In addition to chat.meta.stackoverflow and chat.serverfault we just brought up chat.superuser.com:
It's only appropriate that, after adding per-site metas, we would also add chat to complete three out of four sites in the original "trilogy".
superuser.com Q&A; for computer enthusiasts and power users meta.superuser.com community organization and discussion about the site itself chat.superuser.com real time chat "third place" for regulars
Although chat.superuser.com is technically another public beta, we're still on track for releasing chat network-wide in a few weeks. However, stackoverflow.com will be the last site to get chat because its immense volume presents the hardest challenge.
We're hoping to get good feedback from chat.superuser and chat.serverfault before proceeding onward, so please -- jump in and tell us what you think!