Check this two roadmaps :




I think AMD choosen to Show us the die of Orochi. A BD core seem to be canceled, i would say BD1.
It's clear the second roadmap is less old, with thuban and AM3r2 for BD.

So i think Orochi was BD1, Zambezi is BD2, the real BD incoming.
And lynx maintream have a GPU on die, it's not for only low end. !!!