I wrote a post on my blog Image Alt Text - SEO or no SEO, and I wanted to get some more opinions on it. I know that image alt text for SEO purposes has been hotly debated by SEO's for years, but my post shows how the right alt text can make big differences (and allow you to compete with huge sites like YouTube and Wikipedia) when used on long tail keywords because of the "relevancy" factor. Please read and comment - I'd like to hear what everyone has to say.