I noticed a lot of chatter between lady friends of mine two months ago. I got one to invite me for a work (ie. Fake) account. I've been casually pinning stuff for a few of my sites over the last two months.
I haven't scaled it up yet, but so far I see theoretical potential, but little real outcome yet. My account is indexed in google but none of my pins are. Some pins that I repinned are indexed and show up with my username if I do a site: pinterest.com search. So I know it's being crawled. Last night geared up a massive SB blast on those pins. So far bookmarking hasn't worked. If that fails, then I will try retweeting them.
I see potential for viral traffic, do follow links, and promoting physical products. Female oriented items like jewlery, clothes etc should work well. For a good pin,
you need to make sure you have a good picture on the page you are linking to.
I think you will have to pin landing pages or 301 them to make sure they can't pull a fast one on you. I've been wondering how they will monetize this monster, so this may be their blackhat strategy for now.
Just typing this has given me some new ideas.