Off-topic sounds great.
For a bug report forum, I really like that idea. We could do exactly what you said--mark them as resolved as we go, and at least acknowledged otherwise.
Then, we could do a "rollup" of all the bugs and fixes into the release notes for each new release--and retire the bug threads since they would no longer be needed. This would also keep things on topic since people would not want not want thier off-topic posts lost when the threads were retired :)
I like being very open, both about the good and any potential issues that are being worked-through. I think we'll set this system up for even the private beta forums for now as well.
Chris