The problem with the iPad, however, is that it's not good for marking up documents. It's great for reading legal cases, but not for marking them up and taking margin notes. Personally, I'm one of those people that gets a lot more out of having paper in my hand and scribbling on it than I do just reading something off a computer screen. I'm really intrigued by this product: http://www.thedigitalink.co.uk/products/capturx-markup-for-p..., which lets you print out PDF's onto special paper so that when you write on it with a digital pen, the markings are reintegrated onto the digital copy. Unfortunately, it's really expensive!
Also, 10" is on the small side for what's ideal. A standard piece of paper is 13" diagonal. I've been looking at the 12.2" Samsung, which also has a digitizer, but Samsung's Android skin is just god-awful. It's a shame nobody makes a 12"+ Baytrail Windows 8 tablet with good battery life...
This product seems to really tackle this niche. Apparently Sony is going to be showing it off this week at the ABA tech show in Chicago.