I've seen a few similar systems over the years. I remember a company called ClickTrax which if I'm not mistaken got bought by Google and some of their features are now part of Google Analytics.
Their purpose was marketing, but the same concept can be applied to user experience analytics. The beauty of their system was that what was tracked was defined by the webmaster - in your case the application developer.
I can imagine as an application developer I would want to be able to see statistical data on two things - task accomplishment, and general feature usage.
As an example of task accomplishment, I might have 3 ways to print a page - Ctrl+P, File->Print, and a toolbar button. I would want to be able to compare usage to see if the screenspace utilized by the toolbar button was actually worth it.
As an example of general feature usage, I would want to define a set of features within my application and focus my development efforts on expanding the features used most by my end users. Some features that take maybe 5 clicks and are popular, I might want to provide a hotkey for, or slim down the number of clicks to activate that feature. There is also event timing. Depending on the application, I might want to know the average amount of time spent on a particular feature.
Another thing I would want to look at are click streams. How are people getting from point A to point B in my application? What are the most popular point B's? What are the most popular starting points?