I use the Notability app to take notes on an iPad 3 with a Targus stylus. The app has an adjustable palm rest area and ignores touch there, and it works pretty well. It also has an option to zoom into part of the page, where you can write largely and yet have the text appear smaller on the zoomed out page -- handy given the large tip of styluses. Overall, it's very handy for having access to notes everywhere due to integration with Dropbox and other services, BUT I don't think I would want to be taking notes that aren't based on a .pdf of lecture slides (or another handout) on any tablet. I agree with azure247 that it's not the easiest or fastest way to take notes vs. pencil and paper. So IMHO, I would avoid using it for notes if you're taking them "from scratch" vs. adding to and highlighting .pdf handouts. If you have .pdf handouts that won't require more than highlighting things and writing at most a sentence's worth of words or math symbols per slide or so, it's fantastic.
Maybe before buying the iPad/10.1 (if this is your main reason for buying it), buy a stylus first and try taking notes on a friend or family member's tablet and see if you even like taking notes electronically first. Some people I know get along just fine taking all their notes on a tablet, and it definitely is convenient if you can do it.
