Comment Re:Flash block (Score 1) 485
Filters and scripts can scrub <video> and <canvas> tags. Filtering proxies installed in schools can do this. Security packages used in schools can do this. Browser extensions can do this.
Filters and scripts can also inject a preload="none" attribute into <video> tags to prevent your 100 MB movie from preloading, although this is really the duty of the browser. Some browsers are getting close. Opera can do this with plugins, including Flash. Adding support for HTML5 media should be trivial.
Flash is not just video. Keep your Flash blocker for every other Flash-based evil out there, like games, soundboards, Newgrounds-era cartoons, nuisance ads, sites that will never adopt HTML5, etc...