As a consumer of the Diagnostics Source events for Filters, I would like to be able to tell which filters are registered with the system, when filters execute (including each of the various states it goes through - before vs. after) and why (i.e. which controller/view is responsible, etc), etc.

If you are looking for an example of what we are wanting to do with this data, have a look at the following - http://getglimpse.com/Docs/Execution-Tab

The above shows the various filters that have run for a given request.