"And if you really like to live dangerously, a 4-year QantasClub membership is $734 U.S. currently........ Indeed if the partnership breaks up in those four years it'll be a bummer, but I figured I would take a chance. YMMV, obviously."

Even with this you will still be ahead even if they decided to announce the end 2 years into the 4 years membership since 2.5 years AC access would have cost that much. It's a bit of a risk, but I can't see them ending it while the 1 world alliance is around.

Dave