Just to sidle on in here...
I really don't like the "hardwired" theory. I don't believe for a second anyone is born with a particular fetish. With the power of psychological forces (such as association) being constantly reaffirmed, it just makes so much more sense to think that fetishes and deviances are subconsciously developed through experience.
If fetishes were genetic, they would be truly random and have nothing to do with common experience. You could get turned on by light. You could get turned on by cool breezes.
But so many fetishes can be analyzed for their underlying social implications. Spanking is an obvious example. Is it not more reasonable to imagine they're socially developed?
As for the comparison between fetishes and homo/heterosexuality... I'm not sure it holds. Attraction to the same sex is so common and is so general that I don't think it can count as a "deviance" on the same level as tickling. After all, even within tickling, homo/heterosexuality comes into play more often than not. I'm a ticklephile, AND heterosexual. I'm a ticklephile within the context of being attracted to girls. I don't think they're the same category, so I see no problem considering fetishes to be socially developed but general sexual orientation a matter of birth.
Besides, some studies have shown that homosexuals often have part of their brain (hypothalmus... or something?) shaped differently than heterosexuals, which points to a biological, rather than social, determinant.
Sorry if this is derailing the main topic. Feel free to ignore me. 😀
Well, I guess I'll be hitting the ol' dusty trail...