The factor that I see that pushes the wild card to the AL East is Texas. If they continue on their hot pace of April, especially taking wins from their AL West rivals, I see it as diluting the win records of Anaheim and Oakland. Eventually Texas' pitching will catch up to them and they’ll settle down to a below .500. Thus the West will figure a bit weaker overall, with probably Anaheim leading.
The AL Central will settle down as well. I'd say now either Minnesota or CWS but regardless, I absolutely don't see a wild card here either.
So with the weaker West, with Texas stealing wins in the beginning, and with the mediocre Central, the wild card ends up coming out of the AL East.
Just my takes...