I agree with Java/Flash applets embedded into web pages. But I;m not sure I agree with entire sites being designed in such a way without a text-based alternative. To be fair, I'm biased on being fairly strict with accessibility when I code, but I've been to places like colleges, schools and such where you're restricted to no downloads and the browsers don't have the required plug-ins already installed.
Nice article by the way, was a good read