Recently there has been a lot of hub-bub over the whole Pinterest copyright thing. There are lots of people who are worried about getting sued over copyright issues, and lots of people getting upset because people are pinning their images (which, in some cases I guess I can understand, but mostly I don't.) If you head over to The Paper Mama, check out the Safely Pin post Chelsey did. There's lots of tips on how to pin properly by giving credit to those you pin, how to protect your images when they get pinned and how to stop people from pinning your stuff altogether. There's also some free images she's sharing that you can post on your own site stating if it is pin-friendly or not.
Personally, I love Pinterest! I don't use it a ton, mostly I forget about it. I think the last time I used one of my boards was to collect some pictures of pixie haircuts to take to my hairdresser. But I do love it when others pin my stuff. (So long as it's done properly, with the link. Seriously, read the post.)