Boasting a 800-million-user database and reporting close to $1.6B in revenue last year (according to industry speculations), 2011 was definitely the year when Facebook "came of age." Key developments that marked the growth of Facebook last year include the introduction of the Timeline feature, which is now available to all users, the acquisitions of location-based social network Gowalla and mobile developer Snaptu, and more importantly a public apology from founder Mark Zuckerberg on the numerous privacy issues surrounding the network.
