There's a article in the Jan 10, 2013 WSJ by Sanette Tanaka that all real estate photographers need to read and use for their marketing. This WSJ article reports on a study done at Florida International University's Hollo School of Real Estate.
Note: The link above to the article only works if you have a subscription to WSJ online. Anyone can see the article if they google "What a Picture's Worth By Sanette Tanaka WSJ" and then click the second google link (thanks Rupert!). The photo to the right is linked to a WSJ video that summarizes the article but doesn't seem to be restricted.
Here's the essence of what the study found:
The study was done by Ken H. Johnson, associate professor of finance at Florida International University's Hollo School of Real Estate along with coauthors Christopher Cain and Justin Benefield. The study is titled, “On the Relationship Between Property Price, Time-on-Market, and Photo Depictions in a Multiple Listing Service,” published in the Journal of Real Estate Finance and Economics in 2011.
For those that haven't seen the 2010 Redfin study that the WSJ reported on this 2011 study generally confirms the fact that photos on the marketing of increases the net sales price of residential real estate and the counter intuitive fact that photos INCREASE market time. These studies should be the center piece of real estate photographers marketing. Note that these two studies (the Redfin study and the Florida study) are the only hard data that proves that professional real estate photography more than pays for itself!