It's been a tug-of-war between COD4 and Halo 3. Just a few weeks ago, COD4 managed the unthinkable and knocked Halo 3 off as the top-played Xbox 360 title. Then Halo 3 reclaimed the throne last week. Guess what? Call of Duty is back on top. This is a battle that may rage for the entire year. On the XBLA side, Rez HD was the most-downloaded Arcade title in its first week of release.
The Top Live Titles, as reported by Major Nelson, list ranks unique users playing Xbox games while connected to Live. The Top Arcade Titles list is based on the number of full versions sold in a given week.