I've heard of people wanting Facebook to add a "dislike " button, but Facebook is going in another direction for retailers.  It's a "want" button, and Business Insider has the details:

Facebookannounced that it has joined forces with seven retailers — including Pottery Barn, Victoria Secret, and Neiman Marcus — to test the platform which allows users to "want," "collect," or "like" a product. Note: if you "like" something, then the item will show up in your Timeline.

A spokesperson emailed a statement to AllFacebook explaining:

We’ve seen that businesses often use pages to share information about their products through photo albums. Today, we are beginning a small test in which a few select businesses will be able to share information about their products through a feature called Collections.  Collections can be discovered in news feed, and people will be able to engage with these collections and share things they are interested in with their friends. People can click through and buy these items off of Facebook.

Mashable points out that even though this sounds Pinterest-like, Facebook has one upped the pinning website because products within a given collection will also feature a Buy link.

Although Facebook won't get a cut of sales, Robert W. Barid analyst Colin Sebastian told Reuters that the "Want" button provides other opportunities for monetization. "In addition to potentially collecting a transaction fee for referring users to an e-commerce site, Sebastian said that retailers might also pay Facebook to promote products featured on users' wishlists, similar to the way the Facebook's current ads function."