If you go through this line in explorer:

1. d4  d5

2. c4  e5

3. e3  dxc4

4. (Both Bxc4 and Bc4 are listed, and have slightly different percentages though they are obviously the same move)

I'm not sure if this occurrs elsewhere, but thought I would let you guys know about it.

- tease coming ...

I believe in the Bxc4 games, the player of the White pieces actually slammed the bishop down on the c4 square in a violent motion, grabbing the pawn in the process. In the games with Bc4, a gentler motion was used. This latter variation is not considered to be as aggressive a continuation as the former.

hehe. we'll fix this. if you see it crop up anywhere else, let us know!