Google sparked concern this week when it announced that it will be folding users’ personal data into Google search results, including information from users’ Google networks and accounts such as Picasa and Google+

The move has not been welcomed. Notably, Search Engine Land’s Danny Sullivan has posted several examples of searches that show how the new search feature “pushes Google+ over relevancy,” saying that the new feature “clearly” favors Google’s social network over the results of other social networks. The tool also offers users the option to toggle between searching their own personal data and searching the Web as a whole.

Google fellow and search developer Amit Singhal told The Washington Post that the new option was supposed to improve individual experiences by making search results more personal, but many say that the new feature does just the opposite.

Here’s a quick primer on what the program is and what folks are saying about it.

What does “Search plus Your World” do? Essentially, Search Plus Your World, or SPYW as it’s been dubbed by the acronym-happy technosphere, uses Google+ a new source for search results. Related Google+ page and people suggestions appear in a box on the right-hand side of search pages, publicly available content posted by people in your Google+ network on the Web shows up in search results and any content shared privately with you on Google+ will also pop up in response to your queries.

Google+ profiles are also a part of search results now, and are promoted above other results. So, for example, if I do a search for “Elizabeth” in Google with the personalization turned on, Google points me to the Google+ profiles of friends with that name as I type my query and returns links to those profiles in my results.

How do I turn it on? Google is turning on SPYW for you, with personal results appearing throughout search query returns. Users can also choose to search only their personal network by clicking a link to “personal results” that appears at the top of search pages.

How do I turn it off? For specific searches, you can turn off the personalization by hitting the globe icon on the new toggle switch that appears on every search page. If you want to disable the feature permanently, head to the “search settings” menu under the cog icon that appears in the upper right-hand corner of your window when signed into your Google Account. In the “search results” menu, scroll down to “Personal results” and click “do not use personal results.”

What privacy concerns have been raised? The idea of having Google search through users’ personal data — even if it’s data they’ve already agreed to share with Google — is enough to make even the most open person think twice.

Google, anticipating this anxiety, has taken pains to let people know that it’s putting all search results under the HTTPS protocol, so that no one should be able to look at any individuals’ search results and therefore reveal the private content that’s become a part of Google’s searches. The company also, as mentioned above, has made it fairly easy to turn off the personalized results.

But, as the Electronic Privacy Information Center pointed out in its brief blog post on the subject, Google is not making it possible for users to opt our of having their information pulled our of other people’s search results — meaning that even if you decide not to look at the personal results yourself, your Google+ contacts can still see information from your account in their personalized results.

What antitrust concerns have been raised? Those raising antitrust concerns are certainly more vocal than the privacy folks, because of the way that the new feature seems to promote Google+ over competing — and more popular — social networks such as Twitter and Facebook.

Twitter has said explicitly that it thinks the new feature is bad for the Web. Google+ content is deeply integrated into the Web and is easier to access and use than any public Facebook and Twitter data. The antitrust argument is that Google is using its dominance in search to unfairly and artificially prop up their less popular social network.

How is this different that Bing’s relationship with Facebook? Social search is definitely not a new thing, and Bing and Facebook have had a similar deal going for months. Facebook data has been incorporated into Bing’s search results, with small notifications telling you when friends have liked certain subjects or have some relevance to your search queries. On its face, this looks like a very similar deal, a search engine and a social network are working together to showcase exclusive data from that network.

There are two main differences between that partnership and SPYW. First, simply put, Microsoft doesn’t own Facebook. Well, not all of it. Microsoft does own a part of the social network, but Facebook is clearly it’s own company, making its own business decisions. Facebook and Google have negotiated over data before, though they never reached an agreement. Blogger John Batelle has

Second, the Facebook integration is opt-in on Bing, meaning that if you’re not interested in having your Facebook account linked to Bing, the search engine will never know anything about your Facebook account or your Facebook friends. From a privacy perspective, that decision makes all the difference.

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