Comment 29 for bug 316247

Yeah, so, the delegate would have to be passed the complete appcast item dictionary, including all custom keys defined.

The problem I'm having here is that if I do some kind of tagging / branching system, I'd like it to support the paid case, too. You can't just use this technique with a "paid" key to mark paid updates: you'd need to be able to release new updates to users running both 1.x and 2.x if you had, say, a security vulnerability. There's actually a poset involved here.