The rumor was first reported by Cnet Monday afternoon. People familiar with the matter have confirmed that a commenting platform is in the works and that Facebook has been reaching out to prominent media organizations to partner for the launch. We also learned that:
Users can use the platform by logging in through Facebook or Twitter.
Comments are threaded, and can be voted up ("Liked").
Comments can be synced across a publisher's site and Facebook Page, meaning that a comment made on a publisher's site will show up on its Facebook Page, and vice versa.
Currently, some publishers allow users to log in to their sites using their Facebook credentials, enabling users to cross-post their comments to Facebook as status messages or wall posts. The new commenting platform will potentially allow for a much deeper -- and more harmonious -- integration between Facebook and third-party sites.
It's another step in Facebook's ultimate determination to dominate the web, to evolve from a destination site into a service that's integrated into every part of the online experience.
We have reached out to Facebook for official confirmation and will update this post with any further information.