To me companies using consumer hardware to determine whether there's a great need for professional hardware seems silly on it's face. They just don't want to invest the money, which would be fine, but with Darwin's limited use profile there isn't a good way for a company to just jump in and independently write drivers. The only plus I'm hoping for is that Intel's Larrabee might be easily SLI'd between 2 to 4 units and trounce the performance of pro cards available today via OpenCL. If that happens I won't care about Nvidia or AMD's offerings any more.
You'd be amazed at just how similar the professional cards are to the consumer units. Take the same GPU, add additional VRAM, modifiy the firmware, and develop new drivers. That's about it.
In practice, it does typically mean different PCB's to hold the additional VRAM, and maybe a larger ROM (or muliple ROM's) to contain the larger firmware. But the GPU, is the same if possible, due to the development and manufacturing costs. They can make different parts (i.e. change the address registers on it), but it's more cost effective to limit/allow features in the firmware.
It's just systems engineering to create the different models.
More work is placed on the software developers IMO, as they have to enable these features in their products, assuming they want to support it. But I'm under the impression, it can actually reduce their workload in the end (i.e. use some code to access the card's features, instead of trying to program their apps to do a specific function for a card that doesn't already support it (i.e like RISC vs. CISC instructions in days past). The compilers had to be developed to do decode complex instructions to a series of simple instructions in RISC based systems to perform the desired task.
Seems parallel to me. More work on the front end, but the payoff is worth it, and saves time in the long run. Ultimately, the users would certainly benefit, and it could give a notable edge. Especially in MP's, as Crossfire and SLI aren't supported to assist in brute force calculations.