It's a proposed Q&A site about bikes. The exact focus has not been fixed yet--if you would like to contribute your thoughts, please do so. However, it does seem to be leaning towards bike maintenance currently. For an example of what the site would look like, see http://cooking.stackexchange.com/ or http://superuser.com/. It's a really slick and efficient site design, so I hope you all will be interested in contributing.