The Wayne State University Center for Urban Studies uses Google Earth to make its research on Michigan neighborhoods and changing neighborhood conditions available to policy-makers and citizens. This mapping-system was developed by Dr. David Martin of WSU's Center for Urban Studies. The system uses the Center's research databases in conjunction with Google Earth. Just open the .KMZ files with Google Earth and start exploring!
http://maps.culma.wayne.edu/takingstock - This link features several of Dr. Martin's Google Earth Applications including vacancy data provided by the United States Postal Service.
Change in Address Vacancy 2005-2009.kmz (431.00 bytes) -
Michigan Residential Address Vacancy Data 0909.kmz (430.00 bytes)
You may need to open these after you have opened Google Earth.