You didn't mention US. Did you consider it? Many consider it the worst of the legacy carriers, but they do have free upgrades, free companion upgrades, great upgrade percentages, and are in the Star Alliance. I've been very pleasantly surprised. In addition, they have a challenge program (normally $215 after tax, but free through the end of the month) that lets you get Silver status immediately and lets you earn and keep Silver/Gold/Plat/CP status through 2/2011 if you fly 7.5k/15k/22.5k/30k miles in the 90 day challenge.