Last year, Mozilla introduced this nice tool that helped Firefox users keep their plugins up-to-date. Today, Mozilla announced the expansion of this plugin check coverage to work with Safari 4, Chrome 4, and Opera 10.5.

Outdated plugins are a major source of security and stability risk for web users, and some studies have put the proportion of users with older versions as high as 80%.

Just visit mozilla.com/plugincheck/ to run a plugin check for your browser.

You should also check out SecBrowsing, another powerful tool that helps you keep your browser and plugins up-to-date. If you are using Google Chrome, there is a SecBrowsing extension that alerts you if plugins are out-of-date.