In all seriousness, I think it's the first great leap towards the end goal of touch-computing, and the death of the mouse as a navigational tool. One could argue the iPhone OS in general was, but until that tech revolutionizes the way we navigate an OS on our computers (or larger devices), we'll be trapped by mice.
I rather like the idea of navigating my computer, entirely by iPhone-level touch responsiveness. In fact, my only real complaint about my iPhone (besides the fragility of it) is that it is not a full-sized computer. However, after a few years of using an iPhone, I rather dislike the experience of sitting down on a PC, dragging a stupid cursor icon around to accomplish tasks. Mobile Safari is a much better (and faster) experience, for navigating websites. Google Maps is much more intuitive than loading up the actual website. Touch-operated OS (along with gestures) is the future of computing. And that doesn't just mean 'tack on touch gestures', like in Win7 -- the OS needs to be completely build on it, from the ground up. I think this tech will really take off, once they load it into all of their computers, atop of a full OSX install. My guess is that OSX.7 will be able to run in either environment.
Thumbs up from me. To the future! Now, if only they could build a more powerful device, include some multitasking and give me a flash plug-in...
In all honesty, I think we're going to see the same kind of thoughts about the mouse in five years, that we're having about old cell phones, today. Touch interface is going to make us think "why did we ever use a mouse?", much in the same way people think "how did we ever live without the modern smart phone?"
If I had the cash, I could see myself using this on a daily basis. It's a nice, book-sized touch computer --
Star Trek-style. But, like you, I don't really see a point in owning it, having an iPhone in my pocket. But I can easily see something like this being a requirement for school kids, twenty years from now. Instead of buying hundreds of dollars worth of paper books and supplies, you just bring your iPad to school. The teacher syncs your assignments to you, and your 'timed tests' are locked out when the time runs out (no 'drop your pencils' cheating!).