Yes, please review the below video for a audio\visual demostration.. plus a cat. www.mattcutts.com/blog/matt-video-alt-attributes-for-images/
Hi, Yes, I have seen this before, but it doesn't answer my question... Does the ALT tag only affect your ranking in 'Google Image Search'?
First, there's no such thing as an alt tag. There is, however, an attribute of the IMG element called alt. Second, that's a separate question. The answer to that is it'll have an impact on your regular page rankings, but the impact will be minimal at best. My advice? Don't use the alt attribute to stuff your keywords. Instead, use it to provide a textual equivilent of the image.