It should be obvious to everyone when you use the same game engine for every sequel, the only people working on the sequel exclusively are the, data collectors, map makers, and campaign builders. BlackSix is a campaign builder and is working on the Sequel exclusively. The majority of the development crew will be working on aspects that apply to EVERY sequel, the Game Engine Code, AI, Commands, FM, DM, Trees, Water, Clouds, Dynamic Weather. Not sure why this isn't obvious. Also some of the aircraft being built for the sequels will be used historically on the COD map aswell, so even some of the aircraft modelers aren't working exclusively for any particular sequel.
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Intel core I7 950 @ 3.8
Asus PT6 Motherboard
6 gigs OCZ DDR3 1600
Asus GTX580 Direct CU II
60 gig Corsair SSD [with only COD and dual boot OP system]
500 gig HHD
LG 37" LCD
MSFF2 Joystick
Cougar Throttle
Saitek Pro Rudder pedals
Voice Activation Controls
Track IR 5 ProClip