Despite an initial download glitch, fans have now downloaded more than 1 million copies of the Call of Duty Modern Warfare 2 Stimulus Package, a set of five new multiplayer combat maps sold for $15, in the first 24 hours.

Activision Blizzard, publisher of the game, also announced that 2.5 million copies of the map pack were downloaded within the first week from Microsoft’s Xbox Live online game service for the Xbox 360. That makes the map pack the most popular game download to date on Xbox Live.

Activision Blizzard said that fans have played more than 1.75 billion hours of game play with Call of Duty Modern Warfare 2 since it launched in November. I myself have invested more than 48 hours in online game play (and just recently hit level 54 in multiplayer, which makes me a Brigadier General!). The number of aggregate hours adds up to more than 200,000 years of game play. Oh dear, think of all of the lost productivity we’ll never get back.

Modern Warfare 2 had sold more than 15 million copies at last count. I downloaded the map pack on the first day and reviewed it here.