The posts work in the same way as embeds from Twitter and YouTube. Once your account is enabled, you will have the option to "Embed post." That will produce a code you can cut and paste into a blog entry or HTML file.
For a post to be embeddable, it must be set to public. In its announcement, Facebook used a status update from the British Monarchy about the recent royal birth as an example:
With this in mind, Facebook introduced hashtags in June so users and journalists could track conversations on Facebook about various issues. The new embeds can also include hashtags, which readers can click on to see those discussions.
The intent of such efforts is to provide more inventory to advertisers looking to reach people during live events, like the Super Bowl or the Oscars. Until now, Twitter has offered the lion's share of such ad opportunities, but with 1.1 billion users, 28% of Facebook audience offers a viable alternative.