there's actually a lot of nudity on DA.
but in the world of art, everything is appropriate right, since good and bad is all in the eyes of the beholder.
I can take a crap and smear it on a piece of paper and call it 'the yellow revelation'...

I would use nudity because the female form is just astounding. God's most incredible creation. the nudity would arouse the natural instinct in you and it adds a richness to the painting. it would arouse you just so much to attract your feelings but not to the extent of making you wannna just get it out of your system...that's what porn does.
Nudity also is a reflection of trueness, for me. a nude person doing something just seems more sincere than a one who is fully dressed up. it shows a pureness of heart. maybe because we too often assume something about someone depending on what kind of cloth they wear.
the way I wanna portrait human nature can only be done appropriately when the person is nude.

now some artists would take pictures of their friend's private parts and put them up here. some are nice but some are totally without context and sickening. of course that's just my point of view. I just hope all nude-fanatic artists can have a common sense in seeing the artistic context of their work and think about what they are trying to communicate. perhaps those photos work better on a porn site?