WordPress MU

Is there someplace that has the release notes for the versions?

Trac is probably what you are looking for.

I know about trac, but im looking to see what changes have been made from 2.84a to the current version.

And they are in trac.

http://trac.mu.wordpress.org/log/branches/2.8?action=stop_on_copy&mode=stop_on_copy&rev=1990&stop_rev=1953&limit=100

Nobody does up a neat and tidy official post anywhere with a list of all changes in plain English. Donncha usually does a brief rundown, but that's as offcial as it gets.

(his blog is listed in the footer)