In the current poll several people have touched on this question. Of course it will vary with image but for instance I print a lot of 8x10 paper for workprints etc but usually end up with 5x7, 8x8 or 11x14. I rarely like what I see in 8x10 and often crop to anything other than 8x10 as 8x10 never seems right. I have a feeling it is simply that 8x10 = "workprint" in my mind. Should I get therapy?
Also do many of you that print a lot of 11x14 and larger also do much in smaller enlargments? I find that I really like 5x7 and even smaller final prints especially with a group of related shots.
I can well imagine that printing for sale is different than printing for yourself or friends as I do.