I think that our current test coverage by conventional tools is going to be close to 0%. It's also clear that the community has not in fact "embraced testing." Instead, a hardcore group of around 15-20 people (the "testing brigade" ;)) have, and are driving this effort forward on behalf of the rest of the development team.
I am quite certain that you will not see any "embrace" until testing.drupal.org is up and integrated into our workflow. When the TestingBot starts posting unit test success/failure into the queue, we will see the embrace. I salute the testing brigade for all that you have done and will do. It really is a big and important job. I have never seen such unanimity in drupal like we are seeing for delaying this freeze. Consider it done. No need to keep piling on ...