I'm continually surprised by those who claim there is no practical use for this kind of product. Just at a baseline this thing has to appeal to students. Online, easy access to text books, class notes, video, audio lecture recording, sketching, etc. Then think businesses where carrying around a full-fledged laptop is cumbersome but a thin tablet would work great for light typing/data-entry (like me in healthcare). Add bluetooth keyboard capability and video out and you have everything you need for most business operations in the field in a form factor that is much easier to use than either a smartphone or a laptop.
I agree. People who see no need for a product like this can't see beyond their own little world. I'd buy one just for the convenience of being able to show videos and comps to clients out of my office. Quite often I'm tired of having to haul my $2K+ MacbookPro out into the field just to use it as a viewing device. I only want to take the laptop when I have work that needs done, not as an expensive way to view stuff or surf the web. For client review process, or just taking general notes, I'd love to have something to throw in my saddlebag without worrying about damage or loss. On a personal level, I'd much rather have this to watch movies on than the rather small screen iPod.