Microsoft and Twitter have renewed an agreement to bake users' Tweets into Bing.

Twitter and Microsoft have both confirmed the deal. Bing's Social search Website also includes updates from Facebook.

Google previously integrated Twitter's offerings into search, but the two companies couldn't agree to new terms after their original deal expired in July. "While we will not have access to this special feed from Twitter, information on Twitter that's publicly available to our crawlers will still be searchable and discoverable on Google," Google wrote at the time.

Microsoft desires a larger slice of the search-engine market, which is handily dominated by Google. In July, research firm comScore estimated Google's portion of U.S. searches at 65.1 percent, followed by Yahoo with 16.1 percent and Microsoft with 14.4 percent. Microsoft powers Yahoo's backend search, so the game is essentially Google with two-thirds of the market, and Microsoft with one-third.

The recent departure of Yahoo CEO Carol Bartz (who claimed in an email to Yahoo employees that she'd been fired) will surely kick off yet another rough transition period for the company. Ever since the Microsoft search deal closed, Yahoo has insisted it will continue to expand and solidify its online identity despite relying on Bing for its underlying search architecture.

Rather than challenge Google head-to-head in keyword search, Bing has focused more on exploiting verticals such as travel and entertainment searches, as well as leveraging partnerships with companies like Facebook. In an eWEEK interview earlier this year, Bing Director Stefan Weitz suggested that the Web's social layer, which includes Facebook and Twitter, would increasingly come into play as a component of the search-engine experience.

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