That mostly just gives you a false sense of security, have you uninstalled your pdf reader as well? If you haven't updated Acrobat reader in 6-12 months (or so) your computer can be hacked by a malicious pdf link, no need to use javascript for that. If you haven't updated IE6 since you installed it you can get hacked by looking at an image. Etc, etc.

Your much more likely to be hacked by using an addon auto updater than having javascript enabled in your browser, javascript security holes are a problem for *all* users on the web, so they get patched rather quickly once found, whereas auto updaters for addons are specifically used by WoW users, so you have less people that can find the security holes, and theres a bigger chance that you loose your account if they aren't found and patched in time.

You can also look at it from the hackers point of view, which is easier, to exploit a javascript bug that means they have to find a hole Microsoft or the Firefox team has missed, even though they work extensively with security. Or try to hack a single website (all they need is to find the password for the webserver) and upload a hacked autoupdater.

TL;DR: Always update your webbrowsers, your operative systems and any addins to your browsers (such as acrobat reader). Don't use auto updaters for your addons. And of course, try to be smart about what you install and from where you get it.