People who constantly point out the inferior hardware of apple products completely miss the point. The hardware specs are not that relevant to people who buy apple, it's the iOS/Mac OS. Apple happens to make the only hardware that comes with iOS/Mac OS, and that's why they can charge whatever they want. As someone who owns…
The Wacom pen for ipad had to have a battery because the ipad doesn't have a Wacom digitizer or whatever in their screen. There are many things to loathe about iDevices, but even if this is any good, the constraint of using IOS will be hard to swallow.
I for one think it's a really interesting option. I think this would be really cool for doing some 2d sketching / painting. Obviously being iOS there isn't anything like ZBrush, but I would think you'd be able to plug it in to your computer and use it like a Cintiq using Duet Display or similar types of applications.