Its been a while since I posted an update, and this will probably be the last before the final update as part of the Google Summer of Code.
The big update is that I have got pretty decent documentation up now. You may browse it here . Its up to date with the current code base . Besides the user documentation, it also contains some of the internal details about the tools/libraries/design decisions that have been taken in the project.
If you have got some free cycles to spare (human + computer), you may want to give it a shot to try building images for yourself. As a tip, the local mode, involves least amount of setup and is easiest to try out what is in there. If you see anything broken, feel free to file an issue.
 Documentation: http://on-demand-fedora-build-service.readthedocs.org/en/latest/
 GitHub: https://github.com/amitsaha/gsoc2012_fbs