A developer of Star Wars Galaxies just made an entry in their developer diary about the animation system used in SWG.
Hey all, Matt "AdeptStrain" Boudreaux here. I'm one of the programmers for Star Wars Galaxies. This dev diary covers our animation system that we use to create and play all those great moves you see in game.
Before I was a developer for SWG, I was a player. I remember when I first created my character -- a professional campfire-making Wookiee if you were curious -- how great the animations looked. Every gesture, every attack animation, and every dance looked incredibly life-like and natural, despite being applied to an 8 foot walking ball of hair, so it was quite a treat when I was hired by SOE to get more acquainted with the animation system and learn how it works.
The animation system in SWG is based on skeletal animation. This means the artists set up a series of bones, create animations using those bones (using motion capture or crafting them by hand), and those bones then affect the various character meshes they are actually assigned to.
There's a lot more to check out here.