Not what you are asking, but having been through a property search recently, there are some key features I can suggest.
1. Popup the floor plan in the hover window. 2. Add the sq. footage (usually available from the floorplan) 3. Add a 'hide this property forever' button.
2 and 3 were on that Globrix site, but Nestoria have decommissioned it now that they've bought it.
Also, an 'Arrange a viewing' feature that didn't feel like you were endlessly typing your email address and details into a black hole would be nice.