[quote name='youngavatar']just a reminder to people getting the xbox version that you get a download voucher so you need xbox live to play the dlc.[/QUOTE]
Just to clarify, you don't need Xbox Live Gold to play the DLC. You need Xbox Live Silver (which is free) to connect to Microsoft's server, go to Redeem Code and enter the code in the voucher, and start the download process.
Once it's downloaded, you don't have to ever connect to Xbox Live to play (in other words, the content can be accessed offline).