Or as I like to call it "plugin is the web browser". That's one of the things that really annoys me about hate for flash and love for javascript. People don't seem to understand that what you are actually doing is just changing the language and instead of letting one environment to execute the content you depend on another environment to execute it instead. And that other environment is basically just as random, finicky, and instead of one player implementation you now have multiple implementers who don't seem to be able to agree about anything.