Integrated wifi!, yes this Zaurus will have integrated wifi
It has a larger 4 inch CG Silicon screen
Along with the larger screen comes a larger Zaurus overall. I can't comment on exact dimensions, but it's much larger than the 5x00 models.
It still comes with the defacto SD and CF slots
It has USB host, check out the USB connector on the bottom (right side)
It will have a sled, which will of course greatly increase it's size, but also provide an additional CF slot and battery extender!.
Rotation on the fly, when you press and hold the 'light' button, the screen will rotate to landscape
It is designed to be more rugged, and can withstand a drop from approximately 1 meter.
It will have 64mb ROM (like the 7x0 series), and either 64 or 128 mb RAM. Supposedly the amount of RAM hasn't quite been finalized.