All this along with the development of OpenMoko means the tablets will have a tough future if they don't get up to speed with the rest of the worlds hardware. By this I mean the N800 series needs more than just Wifi communications. It needs access to the Cell networks and other up and coming technologies. It also needs better video hardware an a memory system that really is modern.
The possibilities are there but don't discount the possibility of outfits like Qualcom delivering some really sweet chipsets. There is a very strong possibility that some of the first devices delivered could have ARM processors approaching 1GHz.
The unit needs to thing out but maintain a form factor that is pocketable. Nokia needs to get serious about RAM and Flash storage. They also need to clean up the video system. Part of that cleaned up video would lead to a HD capable screen.