1. Can I have access to my data (the side effects of my interaction with an application) in a portable way?
2. Can I stop or prevent others (like the application author) from having access to my data?
I wonder which -- if users had to choose -- they care more about? I think for most uses its #1 unless its very personal data, in which its #2. I love the idea as presented in this article but I'm not so sure how practical it is. I don't know how much overlap there is between "author has to run application a central server" (can't just be a local app) and "author must not retain data".
Seems like a really awkward space to inhabit.