I've always loved going down on a woman. In fact, I ate pussy before getting my first blow job or intercourse (there was a girl in college known for getting guys to go down on her, then kicking them out... I loved that). There's just something about it that's so hot to me, and my wife doesn't seem to mind either.
Like a lot of women, my wife won't let me go down on her if she's feeling "not so fresh". To be honest, it wouldn't stop me. I would bury my face in there after she got home from the gym, if she would let me.