A few months back Google accused Bing for stealing their search results, but now search engine round table reported that Google is indexing about 8 million of Bing image thumbnail results. This issue was first posted by loupiote in Google webmaster forum, he said, when he tried to solve the issue of hotlinking his photo by a content farm site (gasta.co) from bing image results, surprisingly he found millions of Bing cache thumbnail images indexed by Google.
Do read – ALT guide for Image Optimization.
I think this is a small error from Google because they are not copying the results directly, they just indexed the hot linked images from Bing search results, so the fault is on the content farm sites. We had already discussed about why indexing images of a tech blog is dangerous as it may harm your bandwidth of the server.
Now the problem has been solved by Google, search now for Bing cache image you can see only few images on results.