I'm on the edge trying to confirm my suspicion that switching makes sense. I think I'll try A3.

I had 21 AC segments in 2010. Generally full fare, purchased with flightpasses from BOS-YYC. Not enough to hit 35K. This year, I supplemented with an EWR-SIN-EWR on SQ and a couple of Swiss flights. Hit 50K in 2011 but I won't hit 50K each year. Singapore is likely again at 19K roundtrip.