Okay, imagine this situation: Celestia and Luna. Poof. No longer in charge. What happened? Doesn't matter - resignation, coup d'état, suddenly disappeared, whatever. All you need to know is that they are no longer in control of Equestria and the system that has stood in place for thousands of years has basically collapsed as a result. What happens next?

Riots and/or separatism between the different races of pony or the ordinary ponies against the social elite? A series of coups? Invasion by hostile neighboring countries? Somepony else takes over and sets up a new system?

What I'm asking you is, in your own opinion, A) what do you think would happen realistically? or B) What would you personally prefer to happen?