I usually change my oil in the morning before I drive my truck. I happened to be looking something up on Toyota.com and saw instructions for changing oil.
I took a peak and the directions said to run the car/truck to normal temp, then wait 1/2 hour and then change the oil.
I would think you would want to change it cold that way ALL(besides oil filter) the oil would be in the pan. To me the other way doesn't make sense.