Hmmm. Artistic pornography. The 'Art' World sure thinks there is such. Some of Mapplethorpe's distressing stuff comes immediately to mind and where I would think a well-laid and well-lit male member on a table-top is just plain silly, others will rant porn where still others will rave artistic breakthrough - real proof that no matter what the experts (or we) say, 'art' is in the eye of the beholder, be he or her a priss or a debaucher. Very democratic actually. Me, I'm in the 'emotional' camp that some have mentioned.
Genuine museum-level naked-art aside, 99.99% of so-called prurient images displayed in contemporary printed matter, art shows, internet forums and porn sites are shockingly mechanical to me - be they of a member on (or in) a table or of a naked lady on a rock (or something else). But once in a great while a picture has EMOTION AND CONTEXT, the subject (or subjects) BELONG in their surroundings, and everything is right ... and if supremely well-executed, it's art, and it's humanity, like everything else.