In which case, just like above, switch to pen and paper. When you are done with your class, take photos of your notes and then upload them to your tablet. It's not an overly complex workflow as when you are frustrating yourself with stylus and touchscreen. Opening multiple apps might be too complex, but I don't think taking notes with paper then reupload them is that complex.
Well, the discussion is not really about how should I take notes. It's about usability of a tablet. Of course it's absolutely possible to take notes on paper and use tablet for other stuff, but it's like having a razor that can shave everything except the mustache area - just one step from being perfect. I'd like to have a device that can be the only thing I take with me to university, otherwise it doesn't make much difference than carrying a laptop and a bunch of notebooks.
And stylus and touchscreen isn't frustrating at all. As I said, I tested it, and even on a cheap Eee PC it feels not much different from pen&paper, it's pretty comfortable to use.
And if you don't mind me asking, what does pressure sensitivity have to do with note-taking? If it doesn't, then what you are asking for, the iPad can already do admirably.
http://www.youtube.com/watch?v=KWi2n_JtzgY
Palm rejection: check.
Pen input: check.
I just don't like the lag between touch input and visual, but otherwise, it's already possible to do what you are asking for.
Pressure sensitivity isn't necessary but it's still nice, for example, for drawing schemes, where you can easily highlight some things by making them bolder, etc. And generally text looks nicer and a bit better readable if the lines have naturally varying thickness.
The video is interesting, it looks kinda better than the iPad stylus I tried, but what bothers me is that tip of the pen is really huge and the guy's handwriting is gigantic compared to mine. I am not sure if it's easy or at all possible to write in much smaller letters and draw tiny details on schemes/graphs with such large tip of the pen. Wacom digitizer has precision that allows you to easily aim even at a single pixel on the screen, I doubt conductive stylus is close to that.