BioWare really can't catch a break when it comes to DLC. When the latest Mass Effect 2 add-on was released to Xbox LIVE yesterday, server issues managed to put new squadmate Kasumi out of commission. Xbox 360 owners attempting to purchase and download the latest "Stolen Memory" DLC probably already know this.
Kasumi has now moved back to the Cerberus Network, so you'll need to start the game in order to pick her up. Then again, Xbox.com is always a viable option.
Either way, she'll cost you $7.00 or 560 Microsoft Points, and marks BioWare's first premium download for ME2. On top of that, the "Firewalker" DLC is also available for free -- also from the Cerberus Network.