Downloaded the map pack just fine, it actually was a really fast download. However, now when I try to play MW2 it tries to update, brings up the bar that would show me the updates progress if it were to happen, and then thinks long and hard about how to go about acquiring the update and then gets angry and stops. A lot of people are having this problem, it's not just me I promise.

it will not let me update, and goes back to Xbox home page.

Same for me.... I'm just gonna wait it out.  Let me know if anything changes...

 
There is a problem.  Another update coming.  Major Nelson twitted about it.  Just have to wait a bit.

Yeah, just read the tweet too :( too bad I wanted to play before work!

awesome game is awesome. 
 
:E

Seems weird that they couldnt have included the title update in with the stimulus pack download and then just those who havent purchased it would need the download.
 Major nelson seems to be saying hours in the worst case scenario.