My good buddy Tim Hodge has posted an essay of his on his blog looking at the challenges and changes in animation from a 2d/3d lense. Go check it out. It's well written, thoughtful and a very fun read if not a tad crumudgeonly. Kinda like Tim. Only not as ugly. He's also got a fun sort story on the blog and some sketches, too. A real rennaissance man. Check it out.