Just got an email from Ubisoft saying:
"You will receive a free key for the Ghost Recon Future Soldier Khyber Strike DLC
Following your purchase of Ghost Recon Future Soldier you registered to participate in the Far Cry 3 closed multiplayer beta this past summer. That promotion did not proceed as planned, so accordingly we're going to send you a key for a complementary download of the Khyber Strike DLC early next week. Due to processing times, it may arrive after Khyber Strike Launches."
So check your emails if you bought Ghost Recon FS and registered for the beta.
"You will receive a free key for the Ghost Recon Future Soldier Khyber Strike DLC
Following your purchase of Ghost Recon Future Soldier you registered to participate in the Far Cry 3 closed multiplayer beta this past summer. That promotion did not proceed as planned, so accordingly we're going to send you a key for a complementary download of the Khyber Strike DLC early next week. Due to processing times, it may arrive after Khyber Strike Launches."
So check your emails if you bought Ghost Recon FS and registered for the beta.