I'm going to chime in here for a second as a woman and offer my own opinion on this. I think dick jokes are hilarious. Being in a room of people where a dick joke is told, I will laugh. Being told a dick joke by a guy who I've known for a while and am friends with, I will laugh. Being told a dick joke one-on-one by a colleague might make me uncomfortable. In my experience, "creepy" guys will start testing the water with stuff like this. It's not the joke that makes me uncomfortable, it's the fact that if I laugh, I'm not sure if I'm opening the door to invite more discussion about dicks and then sex and then advances that I'll have to shoot down. I don't know any women who are actually offended by dick jokes, but I know that talking about sex in any context leads some men to believe that the woman is interested when she really isn't and that's the can of worms that makes us uncomfortable.