You're quite right: the White side of the exchange variation of the Caro-Kann is virtually identical to the Black side in the QGD. But that extra tempo seems to make quite a difference! I've had very good luck in the few games where I've had the White side of the Caro-Kann. The K-side "counterattack" moves faster, and getting in that quick Bd3 makes it harder for Black to develop his QB effectively
Got some games?
In the exchange variation of the caro-kann black can go for the minority attack on the queenside.
How does this work out for you in your games? Is your attack faster then whitesattack on your kingside? Do you often manage to inflict structural damage on his queenside before he mates you?
I've usually done fairly well but it would be intresting to see games from people that have played this kind of opposite side race in the caro exchange.