12.3.12 5:30PM PT Update
Some players that were eligible for the Specializations post-launch offer did not receive their fulfillment email due to having an invalid email address associated with their Xbox LIVE account. We are working to send affected players their codes via the Xbox LIVE Message Center (which is accessible on both web and console). The text will read as follows, and we expect players to start receiving these messages this week. Thank you for your continued patience, and we will provide an update when all messages have been sent.
Xbox 360 Dashboard message text:
Your Halo 4 gift is waiting! Here is your token to unlock six Specializations in Halo 4. We apologize for the delay in providing this and thank you for participating in our program. See you on the virtual battlefield!