The TechNet web forums are back up. Microsoft changed the URL to address the forums to reflect that the product had achieved RTM (i.e. dropping the "beta" from the URL). It looks like this happened without changing other links to the forum. Anyway, they're back up!
The content on the OCS forums still says "beta", but the RTM is definitely on-topic. I hope that the eye-candy will be updated soon to reflect RTM. It would be nice if this content was also shared with an NNTP feed.
For OCS users wanting NNTP support, there is one newsgroup (microsoft.public.office.communicator) on MS's NNTP Server news:msnews.microsoft.com. Hopefully a richer set of newsgroups will be forthcoming. I'm sure trying!