LEGO Batman 2: DC Super Heroes remains its closest challenger in second, above Mario Kart Wii in third.
Elsewhere, The Legend of Zelda: Skyward Sword continues to yo-yo in and out of the chart, climbing two places to re-enter at nine.
The top ten in full:
1. (1) Mario & Sonic at the London 2012 Olympic Games (Sega)
2. (2) LEGO Batman 2: DC Super Heroes (Warner Bros Interactive)
3. (3) Mario Kart Wii (Nintendo)
4. (5) Zumba Fitness 2 (505 Games)
5. (4) Skylanders: Spyro's Adventure (Activision)
6. (6) Mario Party 9 (Nintendo)
7. (8) Wii Party (Nintendo)
8. (7) New Super Mario Bros Wii (Nintendo)
9. (11) The Legend of Zelda: Skyward Sword (Nintendo)
10. (9) FIFA 12 (Electronic Arts)
Leisure software charts compiled by Chart Track, (C) 2012 UKIE Ltd.
Watch The Wanted play Mario & Sonic at the London 2012 Olympic Games below: