I would be very pleased if you would visit http://www.DiverseBooks.com/V3/ which is my Drupal based Reviews website. I am still working on it but I am happy to show it off now.
Interesting points
-> Heavy use of the Book Review module
-> Imported data from Slashcode
-> Heavy use of Taxonomy terms (which were created automatically)
We have just launched the first version of our new modules, built by Fabio V.
to support one of our core functionalities on p2pAid, which is microproject management.
The code is posted under Forums on the site.
We welcome people to take a look and give us feedback, to set up test accounts and to help us develop new features.
The Synaptic Leap is a non-profit organization providing online communities for open source biomedical research. We're using Drupal for our first two pilot communities for malaria and schisto. We're very pleased with the extensibility of Drupal as well as the quality of the features. Once we get funded ourselves we plan to contribute back to the Drupal community with enhancements, fixes and perhaps even money (if we get really well-funded :-).