Beyond3D had an interview with NVIDIA General Manager GPU Computing Andy Keane about Tesla:
Hmm, and in the long-term then, in two or three years… are going to make Tesla-only chips?
Not at the moment, not at the moment… And the basic reason is the amount of R&D dollars that it takes to make a special chip, the manufacturing side (being able to amortize the manufacturing cost over many many chips)… Today, there are [nearly] no special chips [in the HPC industry][…], and even I would say Intel… their major chip is Xeon, which also shares a lot [with Core].
The market just isn't big enough in terms of volume right now?
Exactly, that's exactly the point.