The newest addition to Google Labs is a mashup of Google Images, Google Similar Images and the visual query refinement tool, the Google Wonder Wheel. Called Google Image Swirl, the new tool clusters similar images based on characteristics found in both the text surrounding images, as well as using some of the visual analysis techniques that I wrote about in Google Adds Search By Similarity To Image Search back in April.
Image Swirl results look a lot like the thumbnails presented in regular image search results, but you can see that there are many images stacked behind the topmost result.
Click on a thumbnail, and the stack expands to show you a cluster of images, related by visual characteristics. Click on one of those, and you’ll get a further expansion, this time based on textual or conceptual relationships.
Image Swirl currently works for about 200,000 of the most popular queries. You can tell which queries have Image Swirl results when you start typing in the search box, as available searches will auto-complete, similar to Google Suggest. Google said it plans to expand the number of Image Swirl results available in the future.