You just restated what I already said. They will sell the parts, not as upgrades, but as OEM replacement parts.
Let's call replacing a
LOWER end piece of hardware with an
UPPER end piece of hardware: an upgrade. Yes? Or no? I call that an upgrade. I'm not sure what you call it. If I buy a Mac Pro with D300s and then purchase a pair of D700s from Apple (at an insanely high price, assumedly), I could put them into the Mac Pro, and therefore
UPGRADE THE VIDEO capabilities of my machine.
Right?
It's an upgrade. We're not going to get into the semantics of what the word means.
Meaning that for any MP, the GPU upgrades will probably be limited to the highest original offerings for that model year.
I will happily take that bet. MR is full of folks that like to prognosticate about Apple's hardware direction and choices without any real clue of what they're talking about. As was previously stated,
several people in the Mac Pro section of this forum were insistent that the CPU wouldn't be upgradeable because it was "soldered on". Really. It was more than one person making the (foolish) claim.
We can see through the OP that those folks were: wrong.
We now have folks that insist that Apple
could hard-code specific CPU IDs into the EFI such that the Mac Pro won't boot if the end user replaces the CPU with one of the available 1600 or 2600 series chips. I offered one of those folks a friendly wager that he was wrong, and that Apple would not in any way stunt the Mac Pro's build by hard-coding CPU IDs in. He won't take the bet.
Now we come to you and the GPUs. Are you certain that, when Apple does update the Mac Pro to 7,1, that the GPUs will
NOT be pin-compatible with the current 6,1? Here are some things to think about before answering and/or taking the bet: Costs. Why would Apple invest $N into developing a proprietary GPU card form factor that will only work on one generation of Mac Pro? The ROI there sucks. What's
more likely is that this is the new GPU form factor for Apple's Mac Pros for the foreseeable future, and that any new ones they come out with will work just fine in today's 6,1. There may need to be an EFI or firmware flash, but, oh no! We haven't done
that before, have we? (See: 4,1 Mac Pros becoming 5,1 Mac Pros...)
Personally, I think you're making some massive assumptions based on very little first hand knowledge.