Engineers from Twitter, Facebook and MySpace have created an open-source plug-in that they hope proves their worst fears about Google’s decision to fold its social results into search — that Google is moving away from its mission to be a neutral directory of the Internet.

The plug-in, created by engineers at the three competing social networks, alters the new Google features that showcase Google+ to include social media results from several social networks including Twitter, Facebook, Google+, Flickr, Foursquare, Tumblr, Quora and MySpace.

The tool uses Google’s own search algorithm to decide which social media posts are the most relevant to the query in the three places where Google+ results are featured: the search auto-complete bar, the “people and pages” showcase box and the search results themselves. The code then reworks these elements to conduct a Google search for the most relevant social media content.

In some cases, Google+ profiles are still the most relevant in search, but in many cases that honor goes, for example, to a celebrity’s older Facebook page, established Twitter feed or well-trafficked Flickr album.

On the Web site for the plug-in, the engineers wrote that they hope their tool proves that, with Google’s new tool, searches for generic terms such as “movies” or “music” wrongly prioritize Google+ results over more relevant content.

“Often these results are irrelevant for users, such as when Google links to Mark Zuckerberg's empty Google+ profile on a search for ‘facebook’,” the engineers wrote on the Web site.

The plug-in is not officially a Twitter, Facebook or MySpace product, but the views expressed by these engineers mirror sentiments raised immediately after Google’s “Search, Plus Your World” announcement that the feature damaged the search ecosystem.

Twitter fired off a quick statement criticizing the move. “For years, people have relied on Google to deliver the most relevant results anytime they wanted to find something on the Internet,” the company’s public relations team said in an e-mailed statement. “We’re concerned that as a result of Google’s changes, finding this information will be much harder for everyone.”

Following criticism of Search Plus Your World, Google said that it would be willing to work with other social networks to enable their users’ personal information to show up in the personal search results, but needed business agreements — something these engineers say they have proved false by using Google’s own data for the plug-in.

“This is clearly not true. The bookmarklet never accesses any server or API outside of The information has already been indexed and ranked by Google,” at statement on the site says.

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