I'm a little bit torn on this, so I'll think aloud on list since I won't be able to be at tonight's meeting...
For externally-reported bugs, BZ is the way to go. The patch, no matter who provides it, should be QA'ed before going into the repo.
For new (or newish content), e.g. a new chapter in a guide, I'm less thrilled about tossing a huge patch or series of patches into a BZ ticket. There needs to be some kind of process, but I don't know what that should look like.
At any rate, whatever process we develop for QA is better than what we've got now.