I ran the Mint update tonight then low and behold the search enhancer came back. I couldn't delete the enhancer because it was part of Firefox dependencies, but I was able to edit browser.search.searchEnginesURL in about:config to make it work. I also tried the addon Google (Language: EN), and it is working as well. I also manually removed from the extension directory.
What pissed me off was that the update broke Opera 10.x (and forced the user to use their broken search enhancer). Manually update to Opera 11 retained the user enhancer extension as well. I looked in opera:config and couldn't find the enhancer extension, but was able to edit the search path in under preference setting.
IMHO, Mint is a great desktop distro, but if this keeps up might go back to running Debian or Ubuntu as my default desktop.