The Get The Data service seems to be getting some traction. There are interesting questions and answers being posted but even more interesting is the quantitative approach to reputation building and community building in general. (Quite distinct from, for instance, Wikipedia or the Drupal community and even more removed from human reputation than Digg).
It would be interesting to see how this scales up. It still has some way to go before proper folksonomies start to emerge. It’s certainly a great tool to have around but the lack of ‘discussion’ space (Get the Data: Data Q&A Forum) may be a bit limiting (or liberating).
The idea of a research community propounded here is not strictly compatible with Get The Data because it assumes a great deal of qualitative research (case studies, histories, ethnographies) but a Get The Data-like interface could certainly make it easier to navigate through multiple research projects.