After a week that saw the top Japanese sales slots shuffle around, this week's charts stayed almost completely static, with New Super Mario Mario Bros. Wii holding on to its crown.
According to Media Create, sales for the week ending December 27, 2009 brought Mario's latest Wii adventure beyond 2.7 million total unit sales in the region. Final Fantasy XIII, which was bumped from number one to number four by Mario last week, stayed at number four and edged past the 1.8 million lifetime sales mark.
Beyond a couple positional swaps, the list of games on the top ten this week was identical to last week's, with one exception: Sega's Phantasy Star Portable 2 for PSP climbed back into the chart at number nine, coming from number 12 last week. Its 44,000 sales bring it slightly above the half-million lifetime sales mark in Japan.
As a result of Phantasy Star's resurgence, Namco Bandai's Taiko no Tatsujin Wii Dodoon to 2 Yome! for Wii became the only game to leave the top ten this week.
Just like last week, Nintendo was the heaviest-hitter on the chart overall, numbering five titles (six, counting its subsidiary The Pokemon Company).
Media Create's Japanese software sales charts for the week ending January 3 are as follows:
| LW | TW | Title | Publisher | Platform | Weekly Sales |
| 1 | 1 | New Super Mario Bros. Wii | Nintendo | Wii | 268,212 |
| 3 | 2 | Tomodachi Collection | Nintendo | NDS | 185,502 |
| 2 | 3 | The Legend of Zelda: Spirit Tracks | Nintendo | NDS | 126,303 |
| 4 | 4 | Final Fantasy XIII | Square Enix | PS3 | 111,705 |
| 6 | 5 | Wii Fit Plus | Nintendo | Wii | 105,427 |
| 5 | 6 | Pokemon HeartGold/SoulSilver | Pokemon Co. | NDS | 74,658 |
| 7 | 7 | Inazuma Eleven 2: Fire/Blizzard | Level-5 | NDS | 68,769 |
| 8 | 8 | Wii Sports Resort | Nintendo | Wii | 67,867 |
| 12 | 9 | Phantasy Star Portable 2 | Sega | PSP | 44,334 |
| 10 | 10 | Professor Layton and the Devil Flute | Level-5 | NDS | 43,254 |