NOFOLLOW ATTRIBUTE Pinterest uses "nofollow" on all outbound links. Pinterest creates more inbound links than outbound links for every pin. These more abundant inbound links are, of couse, NOT "nofollow." DAMAGING/SELF-SERVING ANCHOR TEXT Pinterest creates links using misleading anchor text. For instance, links to mywebsite.com will point to a Pinterest internal page that collects all pins from that website, ie http... pinterest.com/source/mywebsite.com - with the result that the http... pinterest.com/source/mywebsite.com will rank very highly when searching for "mywebsite.com" in an amount proportional the the number of pins from that website. The more a website's images are pinned, the higher ranking Pinterest's page becomes. Another type of link leading to http... pinterest.com/source/mywebsite.com is created from a series of 4 thumbnail images as well. It's clear that Pinterest is engineering a grab of a website's traffic by prioritizing the ranking of its own page with a collection of the original website's images. Outbound links are all given the same worthless anchor text: "Pinned Image." Plus it's a "nofollow," so "mywebsite.com" may be getting penalized twice. DUPLICATE IMAGE CONTENT PENALTIES Unless search engines treat images from Pinterest differently, there is a danger that its copies of images be deemed to be the original, and the originals not be shown in search results for being copies. When an image is pinned, the alt text is used to label the image on Pinterest. Pinners can over-ride it, but most of the time, don't bother. This can create a cluster of images on Pinterest with the same alt text as your own image, competing against it in search engine results. EMBED CODE This code allows any webmaster to display an image posted on Pinterest from its website. Naturally, we're smart people here and we'd just hotlink the image any way we like. In the hands of less literate webmasters, this code, when un-modified, creates 3 links, none of which are no-follow. One leads to mywebsite.com in the same page, a second leads to the Pin page (target_blank) and a third to Pinterest's homepage (target_blank). So, 2 links to Pinterest, one link to mywebsite.com. Hotlinked images receive no special treatment as far as I can see when it comes to duplicate image content penalties. CONCLUSION Pinterest traffic isn't particularly productive in most cases, but whatever little traffic you may gain from pinning your own images on Pinterest is likely going to significantly hurt your image rankings, your keyworld rankings to a lesser degree, while Pinterest's own ranking will rise. Pinterest's linking scheme greatly favors http... pinterest.com/source/mywebsite.com to become a direct competitor agains mywebsite.com, as well as its own homepage PR, which, by design, only trickles down internally. NEGATIVE SEO The potential exists to hurt your competitors, if they allow pinning, if you pin their images enough. They will be forced into a competition with its own images and alt text on Pinterest's servers, and they're likely to lose - while blinded by the flattery and the attention. I'm not suggesting this course of action, only pointing out the irony.