The same thing happened again last week. My outbound flights (SEA-ORD-MCO) I flew G class and got .5 points but on the return (MCO-DFW-SEA) I got upgraded to X and got full 1.5% points. that put me at over 11,000 points in two months. I wish I had known, I'd be platinum now.

Oh well
I wonder if it's going to be a continuing thing?