Short flights - aisle always.

Nighttime, window. Scenic Areas (Grand Canyon, NYC, etc), window.

Long flights - prefer aisle.

What is interesting (perhaps odd is a better word) - is when Mr Sophie and I travel together. He is 6'5 and I am 5'8". When we fly together and cannot get exit, bulkhead, or 1st, I take the aisle in front of him so that he does not have to deal with someone laying their seat back. If we CAN get exit or bulkhead, then we sit cross aisles, as we both hate the middle.