You're overstating this quite a bit. I work for a startup that was an early launch partner for Pages back in mid 2007, and have built and maintained our Facebook application from that time. We have numerous contacts inside Facebook, and they
can be of help occasionally, but they can just as easily turn around and screw us. They stole hundreds of extremely popular pages from us that we built up over years, and they did it basically on the same freakin day that our CEO was having high level meetings on unrelated partnership deals with Facebook brass.
The reason is very closely tied to Facebook's engineering success: there is no top-down control over anything. All the engineers are encouraged to break things and to keep the pace of progress rapid. For developers on their API this is a nightmare scenario. However your claim that this is not sustainable may just be wishful thinking. Facebook craps all over its developers, but it's not clear at all that that price is too high to pay for the continued agility that Facebook exhibits. It's hard to argue with that kind of market dominance. Plus, Facebook is so nimble that if API stability does become a problem they can easily switch gears and focus on it.
In other words, I wouldn't hold your breath for any change at Facebook.