VibeAgent.com is part hotel search engine and part social networking site for travelers.
What's hot: It has user reviews (they're called "agents") of hotels, offers lodgings based on 16 types (including "boutique," "lively," "quiet" and "rustic") and lets you join groups based on interest. I could choose an avatar -- now I'm blond and gorgeous.
What's not: The searches are not intuitive. I tried London but was told, "No hotels meet your criteria." Granted, I was searching for March 17 to 30, but I found it hard to believe that nothing was available.