Agreed on all counts - but I think this goes much, much further then just getting changes onto rackspace's infrastructure. I'm looking forward to the hopeful rise of clouds adopting the stack rather then building their own :)
I got to blog about it on the company's blog too: http://www.nasuni.com/news/nasuni-blog/looking-at-openstack-...
Right now that's just a theory, but if Rackspace actually gets it together to have a fairly short release cycle for code to go from OpenStack trunk to running on Rackspace they could really give AWS a run for their money. I loves me some AWS, but having to deal with the typical vendor-client bug fix relationship just blows. The carrot of being able to fix my own bugs would likely make me kiss AWS goodbye for good.