The full details from the CoD team:
"Call of Duty 3 fans:
We have some news that many have been anxiously anticipating. We will be re-releasing the Valor Map Pack for download over Xbox Live Marketplace next week. Alongside that release, we will also be issuing a Title Update which addresses two key issues that many users have voiced in the forums:
1) When the Ranked lobby countdown reaches zero, the lobby will sometimes boot all users back to the previous menu screen.
2) When the game successfully loads into a Ranked Match, occasionally some users will fall outside of the map.
Because we will be releasing both the map pack and the Title Update that addresses Ranked Match issues simultaneously, adequate time is needed for final testing with a release in the near future.
Thank you all again for your patience during this past few days. Again, we apologize for any inconvenience. We hope to see you all on the battlefield!
-- Team Call of Duty"