Going with A3** would be a stupid option, the turn around times on them are much higher than the 737's, Parts are harder to get, and much more expensive and the aircraft themselves are more expensive to run. With jetstar and pac blue in the market, it would be shooting themselves in the foot to run with the airbus.
As for the 777-300. We had the 4 on firm order, with I think it was another 4? or option, we just firmed up one of the options, no big deal, I believe that firmed option is just going straight overseas to the middle east to be leased.