We all know that detailed ALT tags in your images can help SEO on your web pages, but what about the actual image? For example, let’s say that I wrote a page about “Sioux Falls”. ALT tags and image names aside, would an image of Falls Park help my SEO? I believe it would.
Google developed this type of technology to decipher what is actually in an image with their Google Goggles app. It’s also technology they will be using with their Google Glasses product. It only makes sense that Google would use this technology to also rank search results. A post that has an image of what is being written about is much better than one that contains an image that’s not related.
That being said, I think images can hurt your rankings as well. Most notably, images stolen from other websites. If you copy an image from another website, Google is able to tell. That signal may just force your pages down in the rankings.
If it actual image content isn’t a ranking signal yet, it’s definitely something that will be used in the future.