Originally Posted by gemac
Since you don't mention any current status, let's talk about that too. On AA, you can do a Challenge to get Gold (entry level) or Platinum (mid level) status within 3 months. See the sticky at the top of the AA forum for details. You can then request a comp to UA (or wherever else you decide to end up). See the Status Match Master Thread on this forum. No need to fly for a year without status.
Wow, thank you so much. That's the solution. I can't believe I didn't think of status matches. I worked it all out. I will fly to Europe using an AA partner (LAX-Europe is far), gain Platinum status via challenge, then get a status match on CO or NW, maintain the status next year and then just get a status match with UA once I move to Australia. This is excellent. And I guess after I fly to Europe, which will be this summer, the airlines situation (esp. with NW) will be more clear and then I can decide whom to go with, but there's no point in using anything other than AA to gain status.