The Pin button seems to be working intermittently on my site as well. Sometimes it's there and sometimes it's not. Working with the dynamic mode. Switched it to debug.
Here is a link to my blog: http://www.iwashyoudry.com/2013/08/21/spicy-bacon-wrapped-chicken-with-cowboy-caviar/
(I have it set to only work on posts, not on home page)