On me? Well since I'm a girl, I prefer no hair other than eyebrow and scalp hair. I've had a few laser hair reduction/removal treatments for my underarms, because they grow fast and I get irritated when I shave.. my skin is too sensitive.
I do wax myself though. Whatever is left under my arms, my legs, and my whole bikini area. I've been doing it a while so legs and underarms don't hurt.. bikini hurts, obviously, but it lasts almost a month so IMO it's so worth it.
On men, it has to depend on the man. Normally I prefer clean shaven, though some guys look a lot better with facial hair or a bit of stubble than without (example for me is robert downey jr.)
I think a guy should groom his genital region somehow, even if it is a trim. I think it just looks better.
As for the rest of his body hair? I'd prefer it if he didn't shave anything else. A prickly chest or legs is not attractive. If the guy has a bad case of back-hair or chest hair and doesn't like it, he should get it waxed or save up for laser because shaving just.. blegh. I'm not attracted to a lot of body hair, but I think a fair amount on a guy is nice, and I like a nice happy trail :3