Therese's comment: In this post dated August 7, Pinterest expert and Entrepreneuress Academy leader Melanie Duncan explains how to maximize return from the Pinterest/Facebook interaction:
#1: Get a Pinterest Tab from Woobox for Your Facebook Fan Page
#2: Post Pinterest Links as Updates on Your Facebook Page
#3: Promote Specific Boards on Your Facebook Page as part of a status update.
#4: Promote a Particular Pin
#5: Promote Your Pinterest Contests on Facebook
PS: I specify the date of posts that are older than a few days