@bes Well the original idea was that I wanted something like a "Page" in the aaocial media. Where there is an "Agent" (FOAF term) that can post as itself while others can also post _to_ it like a group. I.e. a group that can generate notices in its own name.
And if an instance should be able to, say, convert a group to a "page" (backwards compatibly subscribable to acct:username@instance.example) it'd have to be in the same namespace to avoid collisions.
Not that it's gonna happen any time soon .P