I'd be very skeptical about the companion cert, until all the details are revealed.
(3) Companion Certificate: This CitiŽ / AAdvantageŽ card offer is valid only for first-time
CitiŽ / AAdvantageŽ cardmembers who apply pursuant to this offer for an account by December 31, 2011. Companion certificate expires 6 months after the issue date. Passenger is responsible for taxes, fees and charges in association with use of companion certificate. Your companion offer arrives in the form of a certificate 8-10 weeks after account approval; details, terms and conditions, certain restrictions, and restricted dates apply and will be disclosed on the certificate. Your discount code must be redeemed in conjunction with domestic travel purchased on your CitiŽ / AAdvantageŽ card. Travel must be booked and purchased in economy inventory. The companion offer will be fulfilled as a 50% discount off each passenger's travel. For residents of Alaska and Hawaii, the companion certificate is valid for round-trip travel originating in either of those two states and continuing to the 48 contiguous United States.
In the past, the conditions on similar companion certs have made them close to worthless. For example, they may require more expensive booking classes (H V M L K or W) that mean that two cheaper class tickets end up being about the same price.