I agree. It would be nice to see a format like Sublime Text's pseudo animated GIFs [0] take off. It's not perfect because it requires JS + PNG + JSON and currently the python build scripts only work well on linux. If other tools started providing export functionality to this format then it could get more interesting. Historically, iterating on these ideas on the client has been a good way to get standards implemented in browsers.

[0] http://www.sublimetext.com/~jps/animated_gifs_the_hard_way.h...