Id also love to know the answer to question 2. Steam is a revolution in PC gaming. I think more people would be exposed to this game and hence buy it, as opposed to not having it on steam.
I personally love it because of the pricing, I picked up all of the theatre of war games and all DLC for $20, whereas on the battlefront website I have to pay $30 JUST for the Kursk and Caen bundle?!!?!