Well, the women here on Lit often times get bombarded by penis pics...most often unsolicited..so they become more like white noise if that is the only thing we are presented with in a pic.
I, for one, want to see something that showcases your personality.
I always love the whole "we are very, very shy" speech before showing everyone their dicks. Trust me, folks, that would be the last thing I would show.
Either way, I think the ladies would prefer to see something other than just a penis.