After watching the latest episode followed by next week's episode trailer, I'm wanting to believe that Zoom is indeed Barry Allen. I say that because on Earth 1, Wells/Eobard created the Flash so that he could get home. The Earth 1 Flash is a "good guy." Earth 2, wells again, created another speedster, Zoom. Now at the moment, we don't know exactly why he created Zoom but I'm going to go on a limb and say that he did that so that he could get rid of the Earth 2 Flash. He thought that he would be able to control Zoom since he groomed and created him. Only problem is that Zoom had other plans as he mentions that he wanted to be the fastest speedster so he has to eliminate the source of the threat which is Barry Allen.
It's quite possible that Wells wants the Flash to beat Zoom so that he can harness the Speed Force on his own, thus setting up a rematch with Barry as a new and improved Reverse Flash thus killing Barry and making him the Ultimate Speedster....so although Zoom is the main villain, I think that Earth 2 Wells is the one pulling the strings as he's lining everything up for Zoom and Barry to meet so that he can face the winner of the battle and claim the speed force of his own. Still, it's too early as my theory will more than likely be garbage, lol.
P.S.
If you notice at the 1:00 minute mark here, Barry is in jail...but what for exactly? I caught this recently while re-watching this episode. I'm wondering how or what this scene will turn out to be in the season. In any case, the biggest mystery is just what has happened to Earth 2 Barry.