Imagine if you could share annotations on a page between a certain facebook group you have, so instead of seeing a public comment annotation section you see onl

Imagine if you could share annotations on a page between a certain facebook group you have, so instead of seeing a public comment annotation section you see only annotations from your group. Doesn't have to be facebook either, I'm guessing a browser plugin will come along that allows groups of people to share annotations, maybe you could even pick and choose whose annotations you want to see. At least that's how I've imagined what they are trying to get at, haven't honestly looked too hard into the concept.