A 400MB patch for Call of Duty: Ghosts on PC has reduced the game's minimum memory requirement from 6GB to 4GB.
While complete patch notes aren't currently available (Infinity Ward has said they are coming soon), Reddit user mkapex1 has confirmed the memory tweak.
Players also note that the update fixes up menu stutter, introduces eSports rules and Broadcaster Mode - the latter featuring first-person, third-person, and over-the-shoulder views.
Updates for Xbox 360 and PS3 will be rolled out in the next few days.
Source: @InfinityWard and mp1st