BookMooch, the online swap service for books, is announcing a set of new features today. We first mentioned BookMooch when they launched last August.
Some of their key updates include a BookMooch wiki as a hub for FAQs, a trend we're seeing with a lot of sites these days. They've made available an RSS feed for users' inventory as well as books you're searching for, so you'll be updated at all times. BookMooch now offers the options to close an account, or go on vacation, which simply empties out your inventory for a determined period of time. Their related editions and Mikko's recommendation engine offer more inclusive ways to find what you're looking for.
BookMooch is focused on growth at this point, and looking to increase the number of users that are mooching from their quickly rising number of books being made available to be borrowed. The advanced search options and two-fold recommendation system should help out with that particular growth factor.
See also Shelfari and the MySpace of Books.