the last week I have been dealing with an implementation of code coverage analysis for the upcoming release 1.2 of CakePHP.
Well I started last week and the basic view is already committed. Tonight I will commit the diff view and some code refactorings, which also make the results a little more accurate. Once I commit this, you just need Xdebug installed and are ready to go already in Cake 1.2. :] So it's pretty far along already in my opinion. ;)