From what I recall, Tim had indicated that Beta users would continue to be allowed BYOD access. Once they go public, users won't be given their SIP passwords. Beyond that, I don't know what, if anything, Tim had planned with the purpose of limiting user agents.

I was planning to continue with my Asterisk trunk; otherwise, I'd be bugging Tim for a Grandstream. (As much as I wouldn't mind checking out the Grandstream, I'd much rather keep my Asterisk system online!)