Last week, I have a chance to use the newest version of Toonboom Studio. I think this softwave is much better than Flash when it is used to create characters' movements. Sometimes, I find that 2D animation is more interesting and easier to create than 3D animation. Although it is not as realistic as 3D animation, it has many advantages that 3D animations can never have So far, I believe Toonboom Studio is the best 2D animation softwave. You can also put the animation on the web by import it as a Flash movie.
Check out the offical website below if you are interested:
http://www.toonboom.com/