John Kricfalusi, the mad genius behind the animated "Ren and Stimpy" series, (whose blog is here), recently found a supposed animation expert advising people that animation scripts should be twice as long as live-action scripts because you have to describe every little action and background description and camera angle.
Wrong! says JK: "Animation writing should be short, because you have artists to fill out the visual details. Animation scripts are always too long and storyboard artists have to draw hundreds of extra scenes just to have them all cut out by the studio when they figure out that the show is too long."
The "expert" also advised writers that they should go wild in terms of the number of characters and the background animation because, after all, it's easy for artists to draw just about anything. Wrong again, JK advises: "The responsible way to write for animation is to keep the average amount of characters down to 2 per scene. Especially in TV animation. More characters per scene equals less time to animate each character. This results in cheaper faster crappier animation and no personality animation at all."
Even though I think JK tends to be unduly harsh about animation writers who are not also artists (a favorite rant of his), his blog is well worth following if animation is one of your interests. And there's a lot of merit in his suggestion that if you want to write for animation, it's a good idea to have at least basic drawing skills.