Score one for Team Jacob. Last month Bethesda's Art Director Matt Carofano confirmed in an interview that players could not become werewolves in Elder Scrolls V: Skyrim. While he admitted that there were "currently have no werewolves in the game" he noted "it's definitely something to think about."
It looks like Bethesda reached a conclusion rather quickly. Judging from a recent flurry of leaked images and screenshots it looks like you can be a werewolf in Skyrim after all, though no official statement has been made. The latest leaked video from youtube user TheMadmaniac67 clearly shows the player transforming into a werewolf and ripping apart the enemies limb from limb.
Bethesda still hasn't officially announced the ability to become a werewolf, but watch the video below if you want to spoil the fun. I wouldn't be surprised if it were removed rather quickly. With Skyrim set to release on Friday, 11/11, Bethesda has been fighting tooth and nail to prevent further leaks.
Luckily, information on how to become a werewolf in Elder Scrolls V: Skyrim hasn't been leaked, but if it's similar to how it was in The Elder Scrolls III: Morrowind or how to become a vampire in Oblivion then you should just have to get bitten by one.
Bethesda has confirmed that Skyrim had vampires, but up until now it was assumed that that would be all. It was thought that becoming a werewolf was going to be made possible via DLC, but judging from the video it looks possible right now. We already know vampires are much weaker during the daylight, so it'll be interesting to learn what weakness the werewolf has. Does Taylor Lautner really have a weakness though?