What we really hope to see in the future is a real estate application which allows for relevant property information to be provided to your iPhone via 3G or Wifi as you enter an open house or via a scanned QR Code on a sales sheet. Nearby properties for sale and their information could also be accessible, allowing realtors and shoppers alike to have information at hand while discussing properties. Also, we'd imagine supplementing open houses with guided streaming house tour casts (the Coverflow interface would be ideal for listing details of each room as you walk through open houses). We suspect some, if not all, these services will make it into the home market as iPhones and their smart phone ilk permeate through the public.
Coldwell Banker iPhone site is a nice start. It's very simple to navigate and a perfect fit for the iPhone's capabilities (alongside a good target for potential home buyers). Information input can be a bit tedious, as property searches are not saved, but we imagine most realty agencies will be moving toward handheld experiences like this for buyers to window shop.