Another student shot some video and posted it on youTube.
Moral of the story: whenever going to the UCLA library, be damn sure you have your ID.
UPDATE, 1:51PM: CNN has an article as well, but don't mention the video (no suprise) nor does it mention the unnecessary contact from the police. Rather, CNN states that the student "encouraged others at the library to join his resistance, and when a crowd began to gather, police used the stun gun on him." It also doesn't mention the additional tasings on the ground. And this is a "world leader" in news? o.O