There was a bit of a delay, and quite an uproar in the Android Open Source Project community, but the factory image and binaries for the new Nexus 7 have finally been released by Google. There was trouble around the release, and while we never got the whole story, it seemed to be something to do with Qualcomm not wanting its GPU to be too open...
Source: http://www.phonearena.com/news/2013-Nexus-7-factory-image-and-binaries-available-for-download_id46254
Source: http://www.phonearena.com/news/2013-Nexus-7-factory-image-and-binaries-available-for-download_id46254