Some 3.0 prototype code is making its way onto HEAD (and therefore public svn) but the bulk of the new 3.0 code is still on a private branch until we're 100% happy with the details of the architecture. We wouldn't like for community members to start writing templates and components until we've finalised the APIs, coding conventions, site and content models, etc. as you may have to start over in some cases.
It should all start coming together "properly" in the next 4-6 weeks.
Thanks,
Mike