FWIW, Windows Journal was epic, and nothing on the iPad even comes close (nor really can it, due to the inaccuracy of the input compared to an active pen digitizer). I provided some more details on this a long time ago on Quora (which kind of sucks, but it at least saves having to go into a long description ;P).
OneNote is incredible, couldn't find anything close on iPad - but feels like zero effective marketing there. If Apple made anything like that it would be all over their keynotes and ads as a USP.
Pen and touch computing are not competing technologies: you could have one or the other, or both, and the experiences would be complementary. Touch seems to have led to a much larger market than pen, which is still quite useful, just not something that everyone would wind up using like touch.
Would love to see Apple get into Pen computing, and this is one area where I think Surface could have really distinguished itself (including a digitizer on a low-end Surface RT, for example).
The problem with Pen computing is that it's too close to Mouse and Keyboard, so NEW user paradigms aren't developed or encouraged.... In short the entire story of MS Office on tablets.
Steve understood with the first iPhone WAY BACK that Touch was the way to go and people needed to be "reprogrammed" how to use it. Remember iPhone was only "Steve's way" for the first 18 months before only a few developers were invited to play too in a proto-App store. The whole path from iPhone to iPad was carefully mapped out with the next piece coming only when enough people agreed with "Steve's way". People still want iPad to be "just a pen based Mac" shows a large number of very important people don't get the subtle chane in HUMAN BEHAVIOR required to take the next step.
http://www.quora.com/Tablet-Devices-and-Tablet-Market/Why-do...