Well, the prices are high ... the card with one processor is approx. 1700 US$ (approx 500 gigaflops, if I understand the numbers correctly), the server approx. 8 000 US$ (at least 2 000 gigaflops, more if more processors are incorporated).
OTOH: a good crunching computer is approximatly 700 US$ and produces much less (260 Megaflops - I may be wrong - but I am considering the CPU, not the GPU). The design costs are not that high: the system is based on existing and well tested GPUs, it is the software which has been changed.
The cool part is the fact that Win XP and different flavors of Linux are supported ... that means that BOINC could be adapted for this hardware and that apps could be developed - and it seems to me, that the software tools (libraries and such) are already done.
Looking at folding@home: the WUs crunched by the ATI-graphics processors are done very fast - compared to those crunched by CPUs - I have the impression that this is similar thinking, and that NVIDIA wants to be competitive in this area too. Competition is good for us.