Apple is slowly removing flash from almost all of their devices. It first started with no support for flash in their iOS devices and now the new MacBook Air ships without flash (although it can be installed manually). But this makes almost no difference to Mac users as HTML5 is the future technology for vide and rich internet applications according to Apple and most websites are already adjusting according to that. Mac users would also have noticed that while using YouTube, their MacBooks get hotter as Flash consumes a lot more CPU cycles than most applications. But you can now install a new YouTube5 Safari extension which makes sure that YouTube videos will be e-wrapped as an HTML5 video stream.
This is not the only option to see YouTube videos without flash as YouTube has its own HTML5 experiment site, but it requires a persistent cookie or sign-in to stay active. Also, it only provides non-Flash videos when there’s no pre-roll advertising on the video you’re watching. While YouTube5 streams videos directly from YouTube servers by recoding the HTML around video itself. You can also download the video directly from YouTube with YouTube5. You can set your standard resolution for videos. It allows you to set your preferred resolution in the extensions’ options.
YouTube5 is a free download for Safari for Mac and PC and you can download it from here.