It took 14 months, but shares of the social network finally topped their initial public offering price of $38 late this summer (now they're even higher). That's because Zuckerberg's mobile strategy at last appears to be working. Mobile-ad sales now account for 41% of Facebook's total ad revenue, and the number of people posting photos and status updates on the go surged 51% in the most recent quarter. Facebook is also reportedly planning to launch TV-style ads that will cost brands up to $2.5 million a day. In other words, investors' confidence in Facebook—and Zuck—is back.