It's like this for everyone, I believe.
I don't think it's that big of a deal, though. =/
The most likely answer is that the person that made the skin didn't anticipate the use of transparent avatars.
ttomthebomb said:
Uh, that looks really odd, but I think that's just client-sided on your end.
It's because of the transparency.
A solid avatar would cover the face.