I am very interested in your "collaborative filtering / recommendation protocols for large communities" work, as I've been toying with similar ideas for a while. If you could say more about your approach or can link to anything I could read, I'd appreciate it very much.
Whpearson recently mentioned that people in some other online communities frequently ask "what are you working on?". I personally love asking and answering this question. I made sure to ask it at the Seattle meetup. However, I don't often see it asked here in the comments, so I will ask it:
What are you working on?
Here are some guidelines