Subconsciously believeing that having the system will make the game release faster? I remember around 2003-2004 people were making killer rigs to play the first Stalker game, and then had to wait another 2-3 years for it to come out.

Either way, building a "killer rig" in the last year will probably mean you'll be playing COD with a lot of the bells a whistles enabled and a decent framerate, just not as fast or as cheaply as people who waited.