In case you didn’t hear last week, Steve Jobs told Adobe what’s up. Flash was a necessary evil, back in the day, to make interactive websites possible. The downside has always been that you have to install a third-party browser plugin in order for the Flash content to display. For entire Flash websites, this means that you can’t view anything unless you have the plugin.
Flash was essentially a way for developers to do things that web browsers weren’t ready for yet. It was a hack, for the time being. The big difference is that now content doesn’t have to be encoded into a movie file that only a proprietary plugin can play. Web content should adhere to open standards, making it available to any platform, and that’s the point that Steve Jobs is making.
Basically, Flash is obsolete.