Movie-trading business model gets boost from revamped site, including social-networking section

Sign up for DVD-trading site Peerflix, and your next movie may arrive at a huge discount, from a stranger in Tuscaloosa, AL.

That Peerflix user, BW866403, is currently at the top of the list of "haves" with 1,230 titles in his DVD library.

The three-year-old DVD-trading Web site banks on two premises: that people buy DVDs and only watch them once or twice and that the model for renting movies is ...