Communication programs would make synchronizing and sharing photos (particularly one-offs) much easier.

Touch-to-focus, touch-to-set-white-balance are pretty awesome and far more user-friendly than comparable functions/processes on today's point-n-shoots (when they're even available).

Applications would be able to extend what are fairly difficult-to-kludgy with todays point-n-shoots (HDR, stitched panoramas, night shots, etc)

etc.