A Google Webmaster Help thread has a report of a bug with Google’s robots.txt handling. Specifically, if you block the useragent googlebot-video, the bot that discovers video content, in your robots.txt file, it won’t necessarily prevent your pages from showing up in the Google Video results.

One upset Webmaster who runs a site named purityproducts.com doesn’t want his pages coming up as videos. He said if you do a search for [purity products vitamin d] or other search combinations, he sees video results. I do also, but I also see him dominating the results page with the top three organic results, then a video result, then shopping results and even later a blog. I don’t see why he would want to block Google Video bot, it just gives him one more link.

In any event, there is a bug because his robots.txt file is blocking googlebot-video which should prevent Google from showing his site or pages in the video index. As you can see, it does not.

Google confirmed the bug, where “thejack” an official Google search representative said:

The robots fix you did should have worked. I’m looking into why we still seem to think that these pages “are videos”.

Forum discussion at Google Webmaster Help.