I looked at these a while back. Really like what they've done with the mouse pad and keyboard layout. I could tolerate a slightly larger screen sacrificing some portability for readability and key spacing.
I feel like I'd end up using it on the tram to/from work or at lunch, so that might work for me. I've fought the urge to get one for a while, because I can't accurately assess whether I would genuinely use it, or if my brain just wants the cool nerdy thing :)