The two biggest disappointments were lack of multi-tasking (soon to be fixed by jailbreaking), and low screen resolution. The iPad is only 1024x768 (http://www.apple.com/ipad/specs/).

They're also doing something interesting with the iPhone screen upscaling. During the presenation Steve Jobs mentioned "going to 2X size being full screen. The iPhone's native resolution is 480x320 (http://store.apple.com/us/browse/hom...co=MTAyNTQzMTI), which is not half of the iPad's resolution. I wonder if they're blanking the outside edges, or if they're doing the equivalent of anti-aliasing the iPhone display upwards...