Even though the sunrise whois at Nominet is still showing ‘Auction’, the ongoing auction has been finalised.
Result of WHOIS query:
Domain name: aa.co.uk
Registrant: American Airlines, Inc.
Registrant type: Non-UK Corporation
Registrant’s address: P.O. Box 619616, DFW Airport, Texas, 75261-9616. United States
Registered on: 04-Apr-2011
Obviously the fact that American Airlines already owned aa.com made this a much more brand valuable addition to their domain portfolio.