With word that Simon Cowell is leaving 'American Idol' after this season to start 'The X Factor' in the U.S., the fate of the 'Idol' juggernaut is uncertain. If Cowell wants to, he could offer up some stiff competition to his 'Idol' alma mater, leaving the show with a big "how do we compete against Simon?" conundrum. However, if he plays nice, he could work closely with FOX and 'Idol' on how to differentiate the two very similar shows. Also, does this open up the door for a triumphant return for Paula Abdul? We explore all of the 'Idol' and 'Factor' scenarios (including Paula) after the jump.