The 30GB iPod outsells the 60GB by a very wide margin. I'd guess far greater than 2:1. It's also thinner and lighter and obviously uses different plastics/enclosure. The popularity of the format was likely the deciding factor. Making a 60GB version would mean additional plastics work and for certain very few sales.

But if I was going to get one, I too would prefer the 60. As it is, I think I'd get one if they made the screen bigger and slapped at least an 80GB drive in it.

Bruno