I think it really depends on what it is, and how it works out with your occupation or future/desired occupation. I wouldn't necessarily be unattracted to someone because of it, but like I said, it depends on what it is and the reason behind it.
on you face? I think that's a really bad idea. I know some girls who have had there eybrows eyeliner or lip liner.
even that's looks a lill weird though so no it never looks good. eyeliner is decent I guess since you can't tell but even then they would probably be better off putting on in the morning w/the rest of there makeup.
I think the majority of men that have tattoos on their face are those big fat bald men that just look horrible. But I have seen a guy not long ago that had a blue tattoo covering a small part of his face and he actually looked really hot. It made him look tough and sexy. But I really don't think many people could pull it off. And any girls with tattoos on their faces would look yucky. Apart from if they have got their eyebrows tattooed on-that's ok.