I recently started getting like 500% more visitors(1933 uniques yesterday!!) to my forums and it's all because an image got into google images. I was wondering, how I can get more of these images into google images? Also is there anyway I can make them sign up etc? I know sometimes when I click images in google it just takes me to the main site instead of the image etc. Thanks.
IMHO image search traffic can be very low quality depending on what your site offers - they are usually more tech minded surfers who are more opposed to clicking ads / buying. Just work out for yourself whether you're wasting bandwidth on all the image searches. As for getting more images into the image search, use plenty of relevant text around the images, ALT tags and good image names.
You can enable google image search of your domains in webmaster tools somewhere .. I saw the setting in my account today and enabled it for my myspace image site.