Last month, Google announced that it is now using Rich Snippets for local search. Webmasters with pages that in some way pertain to real world places, can utilize these to reference those places and optimize for local search results.
As you may know, Google Place Paages contain links to reviews for businesses, and Mike Blumenthal has discovered an interesting nugget in Google's Rich Snippets for Local Search FAQ that pertains to this. The tenth question is: "How will Google treat businesses posting testimonials with review mark up on their own site? Will these be treated as a review by the Place Page?"
Google's answer to this is, "Testimonials will be treated as business reviews on the Place Page."
So, naturally, there are questions about people putting up fake testimonials to make their businesses look better than the real public perception would dictate.
Blumenthal says, "The implications of this are profound in terms of the impact that these testimonials will have on review count. The impact that they will have on tone of the reviews, sentiment analysis and rank are yet to be seen but if they are handled exactly as current reviews are, this too will be profound."
People have been putting testimonials on their sites for years, and really there's no way for consumers to tell how real they are, so that's not really different. However, when these are put on Google's Place Pages, a place where many, many people will see as they simply search for local business listings, they could be a little more persuasive.
As Greg Sterling points out at Screenwerk, popular review site Yelp doesn't include testimonials from companies' sites. Google recently stopped showing Yelp results on Place Pages.