As I understand, ImpEx can indeed import more than one forum instance into vB. In other words, he has some archived, earlier posts in bbPress 1.0, with the current forum running bbPress 0.9. We should be able to import the earlier forum, check vB to make sure it all imported, then do a second import to pull in the current forum.
Has anyone done an import from bbPress as of yet? What kind of issues should we watch for? Do items all import (attachments, avatars, etc.) and do users have to reset their passwords on first access? Any altered BBCode we need to run a cleanup script on?
Any advice appreciated! If there isn't any, we'll forge ahead, take notes and report back.