Bing’s new design for search that incorporates a Facebook-driven social sidebar came by way of some pretty sagacious guidance from a man who’s made a career out of turning the internet into a more personal experience: Facebook CEO Mark Zuckerberg.

According to CNET, during a hackathon in February that included ten developers apiece from Microsoft and Facebook who convened to work on a way to integrate Facebook with Bing’s search, Zuckerberg visited the team to share his vision of what the final product should be. According to Microsoft corporate vice president of search program management Derrick Connell, Zuckerberg addressed the developers and said, “Don’t try to do social by building social on the side. Build it into the experience.”

As simple as that statement is, it had a powerful effect on the engineers. Connell recalls that Zuckerberg repeated that statement several times and, as you can see from the new incarnation of Bing, the developers took his recommendation to heart. Social networking is not an auxiliary feature to search on Bing; it is search on Bing the way blue hyperlinks are search on Bing. Searching for local boutiques or reviews for movies is no longer relegated to websites where you have to discern whether or not you trust the reviewer’s opinion. The inclusion of social aspects to search are have moved beyond the linear and simple. Instead, the Bing/Facebook social search offers up a dynamic connection of any information shared by your Facebook friends that is related to your particular query so you get reviews from sources you’re familiar with and, more importantly, trust. In short, the Bing/Facebook search is the internet equivalent to asking your friend for a recommendation, except you don’t even really need to directly interact with your friend if they’ve already said something on Facebook related to your question.

Given how much disdain has been expressed lately about Facebook’s “walled garden,” the collaboration with Bing is perhaps the greatest demonstration yet that Facebook is willing to lower down the drawbridge and allow others to cross the moat and access the site’s colossal social network – Zuckerberg and company are just extraordinarily discerning about who gets to cross over. The partnership presents a new frontier in what social search can do for people and, perhaps more importantly, could signify the most legitimate threat yet to Google’s dominance of the search market.

Google’s been polishing up its Search Plus Your World social results for the better part of the year, but logistically there’s no way that it can really hold a candle to the social search feature that Bing now offers by way of Facebook. The numbers are just insurmountable for Google and its own social network, Google+.

Zuckerberg wasn’t the only Silicon Valley Sage to point to the direction Microsoft needed to go in with the new Bing. Microsoft Chairman Bill Gates reiterated Zuckerberg’s suggestion, according to Connell, that a person’s friends are likely to be more helpful than some disembodied review from unfounded sources. Google+‘s 170 million users pales in comparison to the over 900 million that Facebook claims.

While the siege on Google’s search dominance is officially underway, Facebook is supposedly already working on its own search engine so the partnership with Bing in integrating the social information of Facebook users welcomes some perplexing speculation. A Facebook search engine is already expected to be a legitimate competitor to Google yet now it would have to distinguish itself from Bing so as to not appear redundant. Then again, Facebook may have agreed to partner with Bing already anticipating that its own search engine would be different than what Bing would become, thereby creating two irresistible challenges to Google instead of just one. Even if the two are somehow distinguishable from each other, you have to imagine that Facebook, with its notorious reputation of hoarding all its users information for itself, wouldn’t undermine its own source of wealth and power – user information – so easily, and much to Facebook’s own detriment.

Then again, Zuckerberg didn’t get to where he is today by entering half-baked partnerships.

At any rate, Watch this space to see how the new Bing/Facebook search alliance shapes up over the next year or so.

Do you think Google can counter this new offensive from Facebook and Microsoft, or is it just going to be left out in the rain while Facebook forges ahead in the world of social search?