Anyone who claims that they know whether or not the tube Mac Pro's GPUs will have upgrades available is either lying or works for Apple.
The one thing I will say is that some people should already be smart enough to know Apple never, ever, ever does mid-cycle GPU upgrades as policy. So no GPU upgrade appearing for the nMP yet is not evidence one way or another.
I would assume it hasn't been ruled in or out because if Apple does something like un-gimp the power supply they can't put a higher power draw card into the older tube. But if the new tube uses a similar design it could be a possible option. We won't know one way other another until the new machine shows. Apple may know by now which way they'll go but I seriously doubt anyone in this thread does.
The one thing I will say is that some people should already be smart enough to know Apple never, ever, ever does mid-cycle GPU upgrades as policy. So no GPU upgrade appearing for the nMP yet is not evidence one way or another.
I would assume it hasn't been ruled in or out because if Apple does something like un-gimp the power supply they can't put a higher power draw card into the older tube. But if the new tube uses a similar design it could be a possible option. We won't know one way other another until the new machine shows. Apple may know by now which way they'll go but I seriously doubt anyone in this thread does.