Couple of years later, https://beta.bitcointalk.org/ is up, but no migration still?
beta.bitcointalk.org has advanced a lot since then. Work continues. I think that technically it would be possible to migrate ~now -- the database migration code has already been written --, but I want to be absolutely sure that there will be no issues. (It'd be nice if there was more beta participation...)
I don't think that many people are aware of the new forums, maybe launching an official beta testing event could help recruiting more users.
(Suggestion: They can also be more interested if they could earn few cents for every bug reported.)