Flash powers almost all the video on the web nowadays, so it’s obviously good enough. But is there a better way? YouTube , and now Vimeo , who’re both giddily jumping into bed with HTML, sure seem to think so. Vimeo’s new HTML5 system is just like YouTube’s, in both execution and technical details, in that it’ll only work with a few browsers—Safari and Chrome, for now—and that it’s compatible with most, but not all, of the company’s video libraries. It’s something that most people won’t bother to try at this point, and if they do, they’re probably be underwhelmed, since HTML5 video playback is almost indistinguishable from Flash video playback. (Moving pictures!) But it’s primed to be something that everyone ends up using, and that would be a Very Good Thing. Flash video performs terribly on Mac OS X and Linux, and on the few mobile devices that do support it, playback is uniformly terrible.

Original Source of First YouTube, Now Vimeo: How HTML5 Could Finally Kill Flash Video [HTML5]