So there is nothing different or noteworthy about this part number iPad? I just picked up a refurb on Amazon to give to my grandparents and it turns out it has this model number. The display is markedly inferior to my 'MC769LL' iPad 2 when compared side by side, the MC960LL has much, much less contrast. From what you say it sounds like that might be due to a poor refurb job rather than something particular about this model though. I suspected it was an international version, from some 3rd world region that got iPads made out of Foxconn scraps or something.
Interestingly though, I just registered it at My Support Profile along with my MBP, my own iPad 2, and an iPod touch...as soon as the MC960LL registered it flashed on screen and dropped right off the list of registered devices. I tried to input the serial again and it says 'You've already registered this device'. I also got an email confirmation for registering it, but not for the other devices. Very strange.