We don't currently have anything built in to do that kind of thing but I've been thinking about making an add on product to do all kinds of interaction logging.
You can track link clicks with google analytics and they give you a good idea of how much time users spend on specific pages. But their policies do not allow you to attach any kind of data to personally identify users in google analytics. ie they do not allow us to store userids or anything that can tie directly to any user database we may have.