Arguably one of the more important tablet apps released in recent memory, Facebook for iPad has launched and promises to fill a hole that many have said has existed since the iPad launched in April last year. It's a fundamental break from the earlier iPhone design, however, with new metaphors and some touches specific to the larger screen. We'll find out in a hands-on whether it's worth using over an alternative like Friendly as well as learn how the long-rumored Project Spartan fits in.