I reckon they will proceed to a democratic election. Everyone knows that the army there is very much in bed with the US and at the moment they are trying to bring Israel under control. The army were told by the US to sit back and watch the revolution sweep past them serving two purposes, they have sent a very clear message to Israel and they may have been able to help destabilise Iran.
The people have demanded democracy and will take back to the streets if a military junta emerge. If the US are seen to preside over a brutal suppression of an entire populace they will very quickly see the fall out so their only option at the moment is to broker the introduction of a genuinely democratic government and hope that the people move towards moderate politicians rather than Islamic extremists.
The US will of course have a preferred candidate. Who knows how fair an electoral process there will be? I think we can probably make a guess.
That’s my theory anyway.