I've seen one other NAH (also in the Boston area - Burlington, if I recall correctly), although I see a fair number of other 2007 and later Altimas on the road. Nissan has not been pushing the NAH, as far as I can tell, even though they are available locally.

The Prius is (not surprisingly) far more common. My office parking lot commonly has 3 Prii, 1 Civic Hybrid, and 1 NAH.