You could restrict the beta to developers who have actually shipped an application (that wouldn't prevent them from installing it on their "friends" devices, al

You could restrict the beta to developers who have actually shipped an application (that wouldn't prevent them from installing it on their "friends" devices, although this could probably be audited). I guess this could be a problem for developers whose plan is to develope their first app for a yet-to-be-released version of iOS, but I'm guessing that is an edge case.