Webmaster Help Center - What does it mean to opt-in to enhanced image search?

Opt in to the "enhanced image search" within Google Webmaster Tools and then people can use your images within Google Image Labeler, which will improve your site's images labels/tagging.

I expect Google will then begin to use the public opinion / zeitgeist in addition to your own keywords in the alt tags, which must be a win-win for most websites.

It will be interesting to see if more images searches begin to generate to web traffic on sites that opt in to the enhanced image search.