I have been fiddled with Java Plugin on Google Chrome for a while but having a problem getting it to work even though I follow the steps on many websites. I finally tracked down the issue. It seems that Google Chrome searches for installed JRE plugin by querying
HKLM/SOFTWARE/JavaSoft/Java Runtime Environment/BrowserJavaVersion
If the value in there refers to the version older than 1.6.0_10, it will not work. To fix it, you need to install JRE with version 1.6.0_10 or later then modify this registry key to point to the version that you just install.. then Voila!