We just killed a thread for the same question didn't we?
but I am officially in the "it makes no difference category".
Typically I see people turning the switched receptacles upside down from the others as an aid to identifying them later.
The only time it does seem to matter is when you have a right angle molded plug. I have examples of cords that come out each way though and my UPS cords seem to come out at 45 degrees (so you can get 2 in a duplex I suppose.)