In one of the talks by Gavin at the Dublin moot, he was talking about releases LTS etc and one of the things he showed was a breakdown of issues in each release per component.

He produced a little graphic from the the tracker component data which showed a sort of quick summary of areas affected by each Moodle release. It was something that the people in the presentation really liked - so I think it'd be a good thing to add to our standard release notes templates - helps people get a quick idea of where the changes are in each release.