Honestly, I was worried when I saw the announced that Microsoft added the Pinterest Pin It button to Bing Image search results. I was afraid Bing would use the opportunity to link the pin back to itself instead of the original source - I am glad I am wrong.
If you do an image search at Bing and click on a result, the "Pin It" button will actually source the original image and link to that.
Here is a picture:
And when you click it, the Pinterest window pops up and as you can see in the URL bar, it is sourcing the image source and not Bing:
Anne at Threadwatch asks, "I wonder if Bing search will follow no-pin tag and keep those images off sharing." Probably not but I assume Pinterest will.
Forum discussion at Threadwatch.