I'm a girl, and ive shaved down there a couple of times. heres why i dont anymore.
1: you have to shave practically every day, other wise you get gross looking stubble
2: shaving everyday is painful, as the skin you irritated the hell out of on the first go is probably still feeling a little tender, and dragging a razor down there is like rubbing salted sandpaper into an open wound (yes, its an exaggeration, but it gets my point across)
3: the itch, OH GOD the itch. see, all that hair has to grow back, and in a hurry, to replace what was just mowed down. so grow it does, and this itches like a bloody bitch. naturally you want to scratch it, with good reason too, but do you really want to be seen snatch-scratching? no, thats uncouth and low class behavior.

My verdict: if you want to be bare down there I advise you either wax, some form of hair removal lotion, electrolysis, or laser hair removal, whatever you can afford. and if any of these sounds unappealing, then go natural, with an occasional trim, you'll be much more comfortable.