Facebook announced today that it is releasing some new features for the Like button social plug-in. There is now commenting for the iFrame version, publishing to connected users via the Graph API, and "more robust" analytics.
"Now, when a user adds a comment to the iFrame version of the Like button, a larger, more prominent story will be shared with the user’s friends. In the past, we’ve seen comments result in increased distribution and referral traffic," says Facebook Platform product manager Austin Haugen.
"We encourage websites with objects that people may want to more permanently connect with, such as a brand or product, to publish relevant updates to its connected users," says Haugen. "For example, publish a special offer to users who have liked a specific product. Simply add a few Open Graph tags to your Web page and click on the Admin Link (only visible to admins) to use the Publisher."
Documentation on how to use the Open Graph API to publish to multiple Open Graph pages can be found here.
As far as analytics, Facebook has added parameters to help you test and optimize Like button performance on your site. With these, you will be able A/B test different types and placements of the button.
More info on all of these new features is available here.