The best-selling games of December 2009 in the UK
01 (04) [WII] Wii Sports Resort - 591,000
02 (03) [WII] Wii Fit Plus - 578,000
03 (__) [WII] New Super Mario Bros. Wii - 540,000
04 (01) [360] Call of Duty: Modern Warfare 2 - 424,000
05 (09) [360] Assassin’s Creed II - 361,000
06 (08) [WII] Mario & Sonic at the Olympic Winter Games - 355,000
07 (02) [PS3] Call of Duty: Modern Warfare 2 - 327,000
08 (__) [PS3] Assassin’s Creed II - 288,000
09 (07) [360] FIFA 10 - 268,000
10 (05) [360] Forza Motorsport 3 - 268,000
Source