Like a full-featured VNC client + lightweight Finder + cloud-based file management. I think a future iPad with more powerful specs will be able to handle this kind of desktop -> iOS portability.
I would love to see better integration between my Macs and my iPad in version 2. A simple Finder app would be perfect. I asked today how people were accessing their Macs from their iPads, and, more importantly, how they were interacting with them once they were in.