Mixpanel: Introducing much better segmentation
blog.mixpanel.com
blog.mixpanel.com
Even showing off some customers setups that are using it well would go a long way.
A good example of where this strategy helped the business is Slicehost's Linux tutorials.
In my experience, this sort of feature lets you ask questions that iteratively lead to more questions, and eventually to useful/interesting conclusions.
I seem to be able to only see 1 weeks' worth of historical data, though, so I am not sure if that's user error or some other limitation.