There are many extensions and applications that let you see all the images from a web page. Another way to do that is to use Google Image Search. Search for [site:URL], where URL is the address of the page. This doesn't work for domain names, subdomains and subdirectories because Google shows the images for all the URLs that start with the name you've entered.
It's not a new feature, it's just another way to use the site: operator.