For me I'd say a bit.

I mostly play female characters because I can play around with their emotions better than any the male characters I produce, but I don't pick character pics based on [i]"which chick I wanna sleep with"[/i]. For the most part it's whatever image would suit the roleplay theme and if that image helps to tell their story. I've had a few times where I've had two images and one is clearly hotter than the other, and yet that over attraction can sometimes spoil the characterisation you are trying to achieve. That is because attractive isn't just in facial beauty or clothes. Sometimes a pose, gesture, or even expression can change a character from somewhat alright to very interesting.