* Remove all of the buttons from the "palm rest" areas (or what would be the palm rests on a full size device). Not sure what to do with/about the "trackpad" (which also looks like it's a second LCD screen as well), but moving the keypad slight away from the hinge would probably be a good idea, for usability.
* Put a 4 buttons on each side of the screen (software pref. for one to be a dpad and the other to be special buttons).
* Put a microSD card slot in it.
* Put a Wifi radio in it.
* Put a GSM or WiMAX radio in it.
* Improve the screen resolution a little.
* Run Android or Maemo on it.
To get more NIT specific:
1) give it N8x0 screen resolution.
2) 2 dpads, one on either side of the screen, programmable to so one can be the button cluster and the other can be the dpad (user selectable for right/left handed use)
3) notice the speakers are part of the hinge arrangement? I like that.
4) by having the "palm rest" area between the key pad and the bottom edge, I think it gets a little bit of that ergonomic feel that I keep harping on.
5) I'd have the screen automatically go landscape when the hinge is open and the screen is turned toward the keyboard ... but otherwise I'm not sure what the right mechanic for rotating between landscape and portrait would be. Perhaps that's a new button for the button cluster? (if we use a dpad, that's 5 buttons, and the current NITs only have 3 buttons in the button cluster).