I'd be ecstatic if they brought out a 10" iBook or something even smaller.
Around the 1kg to 1.5kg would be spot on with a simple DVD player (oh ok, CD burner with DVD player), blue tooth and WiFi, microphone and speakers.
30Gb with a reasonable CPU and about 512Kb of RAM.
Just a simple but light tool for the road warriors (or airway warriors) that are seriously weight/size restricted.
I know Sony et al do them but I don't want one of them.