Carol and I had a chance at the OWC booth to speak to the CEO of Axiotron, the German manufacturer or the ModBook, about the new device. In short, it's going to be a great portable tablet for people who need or want one.
If you are even thinking about it, go on over to the OWC store and put your name on the list. They're making a list, but not taking credit card numbers yet, so there's no significant obligation.
The ModBook is a MacBook bottom with a new pen and touchscreen on top and a small amount of additional software to help with non-tablet tasks. There is no twist-out keyboard, and since it is a MacBook, not a pro, it has no ExpressCard slot. However, neither of these significantly take away from the cool or usefulness of this product.
Your need may vary, but if you are in a position to have to do a lot of standing data entry, the tablet form factor can be useful. Similarly, many graphic artists have found the Cintique tablet screens from Wacom to be useful and this basically adds portability to that feature set. In fact, Wacom's patented Penabled™ digitizer is what Axiotron is using to capture input from the screen.
As an added bonus, you can get a built-in Sirf III-chipset based GPS with the ModBook, making it appropriate for all sorts of mobile applications from photography to accident reporting to insurance adjusting. What's your favorite use?