In the surest sign yet that the once-booming daily-deal space has busted, Groupon lost a quarter of its market value on Wednesday after missing fourth-quarter projections, and revealing that it began taking a smaller cut of deal revenue over the holidays. “The cut in its ‘take rate,’ which some analysts had said was needed to revive flagging interest among merchants in its Internet offers, was a blow to fourth-quarter results,” Reuters reports. “Groupon Inc.’s fourth-quarter results were so bad that there is new talk about firing CEO Andrew Mason,” according to DailyFinance.com. “Though Mason is working to …

In conjunction with its check-in deals program, Foursquare will now accept Visa, Mastercard and debit cards. “Money in the bank,” writes CNet. “That's the motivation behind [the] new Foursquare initiative.” “This is going to be a pretty core part of our revenue model going forward,” Foursquare Product Manager Noah Weiss tells WebProNews. Foursquare will now earn a fee from offers redeemed on the platform from all three credit card companies. The deal comes not a moment too soon, according to Forbes. “Historically, Foursquare has been better at helping its users find ways to spend their money than …

Social scrapbooking sensation Pinterest has secured $200 million at a valuation of $2.5 billion. “There have been reports that the funding was coming, but now it is done, in a round led by Valiant Capital Management,” AllThingsD reports. “Investors … were surely inspired by the site’s run-away 2012 growth and continued success,” CNet writes. “Pinterest, as measured by … ComScore, ended December at 29 million unique U.S. Web visitors for the month.” “The San Francisco-based company has meanwhile zeroed in on translating its popularity into sales by developing services for businesses,” according to The Wall Street Journal. …

Reshaping the mobile landscape, Hewlett-Packard reportedly plans to adopt Google’s Android operating system to run a forthcoming line of mobile devices. ReadWrite.com calls the would-be move “drastic,” and the result of HP “having failed to carve out a place for itself in the post-PC era.” As such, “the world's biggest PC maker … is ready to abandon Microsoft's Windows for its mobile computing efforts,” Business Insider writes. “If true, this would be a big shift in strategy for the once mighty PC maker,” Mashable writes. Still, “getting back into the mobile device market isn't exactly a …

Amazon on Tuesday unveiled a virtual currency for Kindle Fire owners to purchase apps and games, as well as make in-app purchases on their tablets. Slated for availability May, “Amazon Coins” are part of a broader effort by the ecommerce giant to help “app developers gain more money from their Appstore submissions,” The Next Web reports.