Major Nelson has revealed the top 20 Xbox LIVE titles for the week of October 24th, and it's mainly not surprising. Just comparing it to the rankings in late June, the top 2 are still Call of Duty: Black Ops and Modern Warfare 2.
I want to say it's because gamers are preparing for Call of Duty: Modern Warfare 3 in five days, and I'm sure that's having an effect, but without any solid numbers, it's inconclusive. A part of that is because Battlefield 3 and Gears of War 3 are ranked 3rd and 4th, and have likely taken away at least some of their FPS competition.
Xbox 360 Top LIVE Titles
1 Call of Duty: Black Ops
2 Modern Warfare 2
3 Battlefield 3
4 Gears of War 3
5 FIFA 12
6 Halo: Reach
7 Batman: Arkham City
8 Madden NFL 12
9 Forza Motorsport 4
10 GTA IV
Dungeon Defenders and DAYTONA USA sits atop the Arcade titles, which isn't too hard since there hasn't been much activity on Xbox LIVE Arcade. Meanwhile, indie game followers on Xbox LIVE Arcade are busy with clones and variations of Minecraft.