Google Maps has already made one upgrade to its real estate search since introducing it in July, and now there's another why-didn't-they-do-that before? option: searching for property by adding the words "real estate" to a map search.
The enhancement also covers other likely search combinations, such as "homes for sale", and links locations to individual "place pages" which provide you with more information. Google says it is planning further enhancements, though there's no word on whether a wider range of estate agents is amongst them. I think the service is still relatively unintelligent about picking an appropriate zoom level, so that might be a good place to start.
Making it easier to find the property you want on Google Maps [Google Australia Blog]