Most "peeps", actually do not have javascript, and in fact, a majority of browsers do not support it. With all of the issues lately with Javascript-level insecurities, spyware, cookie exploits, etc. many people (wisely) keep Javascript disabled. At least we now have browsers such as Mozilla that can apply a more granular control to Javascript

Remember, Javascript is executed, not parsed. In any case, it won't work with text browsers (lynx, links), won't work with fast GUI browsers such as Dillo, and won't work on WAP/PDA/cell users. It's also a client-side solution, which means you rely on the client having it enabled, and using a browser which can properly execute the code you put in it.

Rule 1: Never trust the client browser.