How pip.io stole my heart. (tylerdmace.squarespace.com)

Thanks Tyler, nice post! Very happy that you're finding Pip.io enjoyable.

So there's hard privacy (only these people can see it), but also a lighter "target" gesture that highlights the post for certain people?

This looks like something Google is trying to do, but in two different products: Google Wave and Google Chrome OS. Pip.io essentially combines these two to make one (imho) revolutionary product.