Greg Stirling writes a great article on the changes that Google has made recently to its maps/places pages. He compares Bing and Yelp as well.
“Yesterday Google formally announced some changes in the presentation of local results on Google.com SERPs. The right rail has been turned into a rich display of Places information, including links to interior business photography in some cases. It brings a great deal more of the Place Page into the SERP and will become a new focus for local SEOs. It also will virtually eliminate any right column ads “above the fold,” when the new SERPs appear.”