After what must have been long nights of hard work, Ed and the team have launched Nestoria. Far from the austerity of Craigslist, this site focuses on the user experience: Strong search functionality, maps, and much extra info (pictures of the neighborhood, nearby tube lines, schools, pubs, etc.).
My favorite visual feature is the display of nearby neighborhoods on the map. One click takes you to the hipper, less-expensive neighborhood next door.
Nestoria is very open about sharing data with others. In fact, their approach to building the website reminds me of the "Native to a Web of Data" presentation by Tom Coates of Yahoo at this year's Future of Web Apps summit. They have hackable URLs, an RSS feed for every page, and will even offer direct access to their database to external developers.
They're are also helping the open source community by sponsoring – among others – the Mapstraction project, which is trying to pull together all the different mapping APIs (Google, Yahoo, Microsoft) into a common abstraction.
Full disclosure: I had taken on a small consulting role for a part of the system design for Nestoria, but do not own stock in the company.