First up in the Call of Duty 4 Variety Map Pack is "Chinatown". This map is a remake of CoD classic "Carentan", but sports a modern look for CoD4's setting.
Full of close buildings (shotgun time!) and a lot of 2nd floor windows (perfect for camping) this map can get pretty hectic. Team Deathmatch and Objective game types work well.
Check out the video with some Team Deathmatch gameplay. I was only using Martyrdom because I was working on the challenge... honest.