its not really a phobia, its stupid to be called a phobia. its more of a "ick" factor. Its icky to them and makes them uncomfortable. And almost a decade of being out I don't blame them. I actually don;t tell people because it turns into more of a hassle then its worth. I also cringe when I see people coming out on TV and what-not, because basically what you are doing is saying Hi I'm Jon and I like dick. Its not really anyone's business. The trouble is that when people are moving past the small talk phase in their time together you do need to start talking about your personal life and that is, at least for me, where the trouble starts.
The thing that gets me is when there is a very masculine man who is also gay, because then there is this potential threat that exists.