I don't think the people of KSA are capable of revolting against their King ... if they do they will be slaughtered since he is backed by USA grade weaponry. There is a reason the King flys his USA Airforce Fighter jets around, its to show the people he means business. He also has public executions as well, to continue to show his strength (I'm glad that i never attended one of those because I have heard from co-workers that foreigners that do attend are made to go to the front for extra viewing).
My point is, as long as KSA has oil and the USA is still the war machine that it is, then KSA will be just fine.