it's fine if they are going on stage for something, whether it be acting, or music, but just for everyday wear... not my thing. but I don't make a judgment of them. I know eye liner doesn't make a guy gay, you'd have to be a homophobe to believe that.
I don't wear makeup myself so it's strange but I really love eyeliner on guys. My favorite famous guy is Brandon Flowers and he rocked that eyeliner. I guess it shows a care for looks but at the same time it shows that you don't care if you're conventional or accepted, you like being creative and different.
personally, I love it. I think its really hot. When I see a guy that wears makeup and stuff, it tells me that he values self-expression and doesn't care what other people think. Besides, it really does make yout eyes pop, guy or girl.