I think people are playing Germans more now because they don't like the Soviet faction as much.
When I first started playing Coh2, I simply chose German because I don't typically like Sov armies in any game because every unit is always an eyesore. When I started playing coh1, I chose US initially because I didn't want to play as the Evil Germans.
Not to mention the reputation that "Soviets" have worldwide (except in Russia).
The thing is if you are going to be an evil warmongering genocidal country, you need to have cool uniforms first. Or else nobody will want to play you in video games.
I think just based on less hate for one particular faction, with the addition of Americans, the numbers of allies vs axis will even out.
So, you like a Genocidal faction, but hate the other one? wow, hypocritical much?