It occurred to me after posting this that Google+ is essentially stealing what was ORIGINALLY Facebook's business model (but which has been abandoned): exclusivity
Because of the slow initial rollout? Even Orkut did that...
No, the very concept of circles is about content being exclusive. The point is that you know who you are sharing it with, of course, but the result is that all content posted is inherently more exclusive than elsewhere. Even the very creation of circles feels like adding someone to a club.
Kind of funny that in 2011, not having an invite two days after the service is announced counts as a "slow roll out"