It's going to be a fight between Gears 2 and WOTLK but we won't know the outcome as this site doesn't track PC sales...
I think WOTLK will do 4-5 millions( WOTLK sales will be very frontloaded, people don't want to wait 2 months to buy an expansion when their friends/guilds have it) or so, not sure Gears2 can do that much before December the 31st....( but probably will lifetime)








