I never really thought about it, until I tapped someone to get their attention in history class last year, and she looked at me and said "DON'T hit me!" I said, "I'm sorry, I was just trying to get your attention," she said again "DON'T HIT me!" I said, "I didn't mean to hit you, I was just trying to get ur attention." She said, "Bitch, DON'T HIT ME."
I just let it go. I realized though, if I hadn't been taking sign, immersed in deaf culture, etc. I would have just said her name rather than tapped her. I don't know, some people are just really sensitive.
Besides eye contact and tapping, there are a lot of other differences between the two cultures. When to hug someone, when it is okay to go into someone's house, (w/out knocking, doorbell, etc.) what to tell someone when you leave a room (bathroom, leaving, etc.), and how much to ask about difficult situations (death, divorce, etc.). Deaf seem to be a lot more open than hearies. It can get confusing when what is nice or polite in one culture in rude in another!