Microsoft is benefitting from a campaign on Zynga’s FarmVille where it traded in-game currency for people who opted to become fans of its Facebook page for Bing. Adweek reports that the campaign has more than tripled those who follow Bing on Facebook, adding about 425,000 fans in a single day. As part of the campaign, FarmVille players were prompted with the offer for currency usable towards virtual items by following Bing, and they never had to leave the game to take advantage of the offer. Adweek says Microsoft s social media team then created updates on Bing’s Facebook page catered to FarmVille players, with one such update drawing 585 comments and 20,000 clicks-throughs shortly after being posted. Microsoft said it’s planning more updates geared towards players of the game along with Bing promotions tailored to its audience of older female users. Read more at Adweek.