I've used pinterest to optimize my site and the result was amazing my site was jumped from #434 to #119 in the first week (and now to be #5 on First Page of Google). in just 3 short weeks.
The trick is we must got our website pinned and repinned by many people this is the hardest part. Most of pinterest users won't doing repin when they aren't like what we pinned.
I do simple thing to outsource it on fiverr and got my site Repinned by 75 people, I don't know how can he did it just search by typing pinterest on fiverr and you will find it on the TOP. Many other seller offer pinterest service on fiverr
As I know currently pinterest is best for Search Engine Optimization for these reason:
1. Once our website pinned it has 3 backlinks counts
2. Google interest in social media signal so it will not tagged as links farm
3. Currently pinterest links are dofollow even the image
4. Even not support anchor text (except the url link), it's still perfect for placing our keywords in description. Google will READ it!!
5. You need to ping the links of your pins to the to get your website increase in Search Engine Optimization
6. Obama The President and Mark Zuckerberg now pinning on Pinterest!
So anymore experiences good and bad welcome on this thread.