Hi Derek. Well there is partly that already in that for each version there is a "new features in 2+(whatever) category" which lists the pages where new features for that minor version are highlighted. Here's the 2.4 one for instance - http://docs.moodle.org/24/en/Category:New_features
It's also inyellow at the top of the main page of that particular docs version - http://docs.moodle.org/24/en/Main_page
However, it's possible of course to miss new features I agree. On the release notes the new features are mentioned with links to docs http://docs.moodle.org/dev/Moodle_2.4_release_notes but again it's possible some could have been missed out.