If you’ve not set your robots.txt file to exclude your image folder then you are probably receiving as much if not more traffic from Google images as you are from Google search. Why? Well Google reports that 15% of all queries made are conducted via their image search facility. So it’s possible to receive tremendous traffic from image search and in fact we’ve had clients who have come to us for SEO that are receiving more traffic via image search than content search.
So is the answer to exclude your images folder from being spidered? It could be but you can also take advantage of brand awareness and what we’ll call contact visits (visitors who start with an image search but will explore a site further upon landing from that image search). Brand awareness? Yes, with properly optimized images and rich media you can control how the image/rich media is displayed in the SERPs. Using relevant keywords in the file name and in the properties summary can have a dramatic impact on how your image or rich media file is displayed.
This same practice applies to pdf’s, word docs and almost any file you can place online. Taking the time to optimize your properties summary tab or file properties is a great way to increase brand awareness online.