Although Activision's Call of Duty 4: Modern Warfare was behind Halo 3 for months on the weekly Xbox Live charts (in terms of global unique users), last week the critically acclaimed shooter from Infinity Ward made its move. For the week of January 14, Call of Duty 4 dethroned Halo 3 as the top Xbox Live title.

Whether Call of Duty 4 can remain at the top in the weeks ahead is anybody's guess, but the fact that the title was the number one selling game in the U.S. in both November and December can't hurt its chances.

Here are the top Xbox Live games, as provided by Major Nelson.

Xbox 360 Top Live Titles (based on unique users)
1. Call of Duty 4
2. Halo 3
3. Guitar Hero III
4. Gears of War
5. Rock Band
6. Madden NFL 08
7. Assassin's Creed
8. Mass Effect
9. FIFA 08
10. Forza Motorsport 2

Top Arcade Titles (Full Versions purchased)
1. Metal Slug 3
2. Boogie Bunnies
3. Omega Five
4. TRON
5. UNO
6. Bomberman LIVE
7. TMNT 1989 Arcade
8. Sonic The Hedgehog 2
9. Worms
10. Marble Blast Ultra

Original Xbox Top Live Titles (based on unique users)
1. Halo 2
2. Battlefield 2: MC
3. Madden NFL 08
4. Counter-Strike
5. Star Wars: Battlefront 2
6. Call of Duty 3
7. Burnout 3
8. Street Fighter Anniv.
9. Fable
10. Rainbow Six 3