The stats track the number of unique users logged in to Microsoft’s Xbox Live service that are playing any particular title.
Halo 3 has to put up with second spot, ahead of another Activision title, Guitar Hero III, in third spot. Gears of War occupies fourth whilst the currently US-only Rock Band claims fifth position.
In the Xbox Live Arcade listings, Metal Slug 3 emerges top, followed by the recently released Boogie Bunnies and hardcore 2D shooter Omega Five. Uno and TMNT 1989 Arcade remain popular claiming fifth and seventh respectively.