The daily deals giant reported 4th quarter revenues of over $500 million, up nearly 200 percent year over year and even up a little sequentially. It also cut back on marketing costs a bit, although it said in its earnings call that it will continue to spend aggressively to grow its user base. But it didn’t turn a profit – though it blamed a big tax expense – and investors punished the stock for that or because they’re gradually admitting the company was overvalued. Groupon CEO Andrew Mason talked up technology and personalization, but Groupon really needs to prove that all that user data can translate into higher deal conversion rates and analytics that its merchants can use to improve their marketing. That would help its ad agency relationships.