I think oral sex can be more intimate than regular intercourse. It's a situation where someone could hurt you very badly physically, and generally I would think you'd have to have trust with someone to do it.

That being said, I've only been with one person, and the thought that I did it sorta grosses me out sometimes, but I think that's because he turned out to be someone I should haven't trusted when I did. I think that feeling I have is because of him, not because of the act in general. I enjoy receiving probably more than actual intercourse itself too lol