I'm up for joining any LessWrong team; I'm most comfortable with Python and C++ (or Javascript, but apparently the package is incomplete); I started looking around at the rules and technical details.
(I heard about it before, and while it's interesting, I don't have massive amounts of free time; participating in a team sounds more interesting)
If enough people are interested, we may want to split teams by language (LessWrongSlitherin for Python, LessWrongRavenclaw for Haskell, LessWrongGriffindor for C++ and LessWrongHufflepuff for PHP, or something).
Aichallenge.org has started their third AI contest this year: Ants.
I mentioned this in the open thread, and there was a discussion about possibly making one or more "official" LessWrong teams. D_Alex has offered a motivational prize. If this interests you, please discuss in the comments!