Yes, butternut squash - same as butternut pumpkin. Butternuts are probably the nicest tasting pumpkins. I don't know what sort of pumpkins you have in America. As Foolestroupe said, Queensland Blue and Jap are pretty common, at least here on the east coast of Oz.

My hubby, whose father had a fruit & veg shop, reckons that dry pumpkins are the nicest. Dry, meaning that the flesh is not moist. The darker the colour of the flesh the better the flavour too.   I suspect that warm climates produce good pumpkins because they would ripen well to a deep colour and drier texture.

Helen