MW2 Stimulus Package Not Working – Patch Fix News Update -
Activision’s extremely successful Call of Duty: Modern Warfare 2 gets its first map pack today, but prevalent consumer media reports say that the Stimulus Package five-map set isn’t yet working as proposed.
The MW2 Stimulus Package, the cunningly named first batch of downloadable content for Call of Duty: Modern Warfare 2, the latest in the hit Call of Duty video game series fashioned for the Playstation 3, Xbox 360, and PCs, was released today after months of waiting. If you’re vague as to how big this series is, think Avatar or Titanic size.
CoD: MW2 sold 4.7 million copies just in first 24 hours of its release, and just 4 months after its release, it’s at present the 3rd best-selling game in the U.S.
The Stimulus Package extension, costing $15 on Xbox Live and limited to the 360 for now, would have additional 5 maps to the game’s content.
An update from Xbox Live representative Larry "Major" Nelson came just few minutes ago, announcing that the required title update has just launched for "Modern Warfare 2" and it will allow folks to enjoy the new maps to the fullest:
The MW2 Title Update is now live! It may take a few minutes for everyone worldwide to get it – our apologies for the delay. #MW2
No communication yet on whether the title update did the work, but we are hoping! In any case, 15 bucks is a lot of money to squander for unplayable maps.

The patch doesnt work. It will allow you to play the maps offline in a split screen party. However you cant play them online and now i cant even play any other gametypes online!! wtf. this is bullshit. i basically paid them 15 dollars to not be able to play the game at all. what a deal!!!
i had the same problem, just delete the stimulas map pack, and youll be playing mw2 in good quality internet connection, it worked for me, try it.