This: http://codex.wordpress.org/Changelog/3.5 is not a changelog. This: http://codex.wordpress.org/Version_3.5 gives a few changes, etc, but no list of files added and removed. Where might I find a list of 'breaking changes'? Actions and Filters that work differently?
You can always use GitHub. WordPress has an official (view-only) GitHub repository, and GitHub has an excellent comparison feature.