neither the ipad nor the Adam have active digitizer and they both have capacitive screens. this brings 2 limitations to note taking: no palm rejection and no pointy styluses.
For the ipad at least, I have seen lately a lot of apps that try to compensate for these limitations by trying to implement palm rejection with software. Perhaps someone with an ipad can comment on how good these solutions are.
The issue with the stylus can't be solve. If you want precision you just have to zoom a lot