Facebook has been accused of starting a "smear" campaign against Google in light of its social product, Google Circles, or perhaps because of social search.

Facebook has been accused of starting a “smear” campaign against Google in light of its social product, Google Circles, but it might really be fighting Google's social search. Social media marketers should monitor how consumers respond to the Google privacy issues Facebook has been “whispering” about as they plan their marketing campaigns.

USA Today broke the story that PR firm Burson-Marstellar was hired to pitch anti-Google stories to newspapers about Google's invasion of users' privacy. One blogger contacted by the PR firm exposed the emails sent to him by Burson, and ultimately, Facebook came clean about partnering with the company.

The PR fiasco reveals the growing rivalry between Facebook and Google – especially now that Google is becoming more social. In fact, the heart of the “smear” was an issue with Google Social Circles – a rumored product that is not officially live. Some say Facebook has mistakenly referred to the feature at hand as Google Social Circles when it is actually referring to the circle of people and social data used to fuel Google's social search.

Facebook reported to Search Engine Land that the main issue is that Google is not giving any options to people who “did not approve of the collection and use of information from their accounts on Facebook and other services for inclusion in Google Social Circles – just as Facebook did not approve of use or collection for this purpose.”

Search Engine Land confirms that Google's social search is not a product people can opt out of, but – after thorough investigation – editor-in-chief Danny Sullivan concludes that Google isn't using any information from Facebook that he “can see.”

Nonetheless, marketers might consider Facebook's point that individuals don't seem to have control over whether their data is used for Google social search – and issues like the recent iPhone Locationgate scandal suggest consumers like their privacy.

This news might be especially troubling for Google in light of the fact that it recently previewed its +1 button. Buzz about the social advocacy button has generally been positive, suggesting that the power of social referrals would soon meet Google search results – giving marketers a reason to tie their sites more closely to Google. Stay tuned.

Katherine Griwert is Brafton's Marketing Director. She's practiced content marketing, SEO and social marketing for over five years, and her enthusiasm for new media has even deeper roots. Katherine holds a degree in American Studies from Boston College, and her writing is featured in a number of web publications.