Activision's modern-day FPS is the most played Xbox 360 game by users connected to Xbox LIVE.

Call of Duty 4: Modern Warfare screenshot

According to Microsoft, for the week beginning February 4, Call of Duty 4 has held on as the most played game by Xbox 360 gamers connected to Xbox LIVE. Over recent weeks the game has been battling it out with Microsoft's Halo 3, which had for a long time been the chart leader.

Guitar Hero III takes third place, Gears of War is at No.4 and Rock Band - still only available in North America - takes fifth place.

The top selling Xbox LIVE Arcade title is the newly released Poker Smash, followed by Rez HD, Chessmaster LIVE, Metal Slug 3 and UNO.