Google Places - Ratings websites effect on overall SEO effectiveness

I just recently accepted a new position as the web director for an automotive group in my area. I have been trying to read as many articles, and absorb as much information as I can about SEO as it relates to this industry. According to this article (page 11-12), when google pulls reviews from sites, it has a large impact on how high a page ranks.

Just wondering if anyone has anymore insight on this, or any links to some actual metrics I can look at to show my manager.

Thanks ahead of time.