The trailer for 'X-Men: First Class,' 20th Century Fox's younger-generation, 1960s-set reboot of Marvel's classic superhero series, has finally found its way online via Facebook. And since we know that all you want to do is stop reading and hit play on the trailer, feel free to do so right away. While it's loading, here's a refresher on who are the creative talents involved and who all is playing which hero (or villain).