I am working on a project that has now required for integration with Facebook.
So I will be working to utilise Facebook logins and registrations on the external site.
I’ll post information that may be useful through the project as I expect over time, that this kind of interaction will become more common.
My early look at the Developer Documentation looks good, seems to be well documented, plus all source code is found at GitHub.
The basics seem easy enough, not even reuqiring an API key to use like buttons via iframes.
<iframe src="http://www.facebook.com/plugins/like.php?href=YOUR_URL" scrolling="no" frameborder="0" style="border:none; width:450px; height:80px"> <iframe>
But things are not that simple, so I am off to read up on OAuth and the like.