Thanks to Major Nelson, we have the Xbox Live activity charts for the week of August 18th through August 26th.  It looks as if Halo 3 slipped to number two once again with Call of Duty 4 taking the number one spot once again.

Xbox 360 Top Live Titles1 Call of Duty 4
2 Halo 3
3 GTA IV
4 Star Wars: TFU Demo
5 Madden NFL 09
6 Gears of War
7 Guitar Hero III
8 Rock Band
9 Battlefield: Bad Company
10 SOULCALIBUR IV

Top Arcade Titles (Full Versions)1 Fable II Pub Games
2 Galaga Legions
3 Braid
4 BC:Rearmed
5 Geometry Wars Evolved²
6 UNO
7 1942: Joint Strike
8 DOOM
9 N+
10 Marble Blast Ultra

The above arcade list is based on full versions purchased.

Original Xbox Top Live Titles1 Halo 2
2 Star Wars: Battlfrnt 2
3 Fable
4 Counter-Strike
5 Fable: Lost Chapters
6 Splinter Cell Chaos
7 Conker: Live Reloaded
8 Doom 3
9 Battlefield 2: MC
10 Call of Duty 3

These lists are based on global unique users connected to Xbox Live or in the case of Arcade, full versions purchased that week.