Sooky, the stuff you mentioned about guys turning everything into innuendo I wouldn't necessarily associate with being obsessed with sex. Yeah, they have to be thinking about sex at least a little bit to be saying what they say but I don't think it counts as thinking about sex in an official sense.
I hang out with people who constantly turn thing into innuendo and it's only because said the right way you can make anything sound dirty or sexual and it's fun. Same thing with sarcasm. It's entertaining to have banter going where it's only lame sarcasm and innuendo to see just how long you can keep it up. Of course it could also be the case that the guys you hang aroudn are just idiots.
Anyway, I only think about sex a few times a day. That's not to say those moments are brief, just that it isn't constantly on my mind and I'm within the age group were if anytime, that would be true.
It's probably more accurate to say that men think about women one every few minutes.