That's the question on the table at the panel Marc Canter is moderating, with Bob Wyman, Matt McAlister and George Kane.
Bob Wyman thinks we shouldn't collect Attention XML data until we have good privacy methods in place, Marc doesn't care if people know what he reads, and I asked what to build to answer my question:
How do you build systems that are not paternalistic but still protect consumers.. but give users control?
They didn't have a clear answer. But I think it's an important question for all of us to address.