I'm a bit ambivalent on this issue. I have several homosexual friends, all of whom I like, but I also noticed a number of things about them I dislike. One thing I felt is particularly annoying is when they (I'm only talking about the people I know/experienced this with) get on their 'all the world is gay' mode, which sooner or later focusses on me. "How can you know you're not gay? I only found out myself when I was 20! You can never be sure!" That's the moment I just turn off my ears. Not only do I think they're talking absolute bullshit, but I also think that my own personal sexuality is none of their business.
Then, there is this other friend of mine. I am quite sure he is gay, due to a good number of things I witnessed from him, even though he would never admit it. In case you know the film American Beauty, picture the protagonist's neighbour (the soldier), cut his age by half and you know what I'm talking about.
This guy is changing girlfriends like underwear (well, not quite, but you get the picture), which always involves hurt feelings on the female side. Most of my friends agree with me that he is a huge arsehole when it comes to this and doesn't deserve any kind of relationship. Moreover, many agree with me when I point out the "gay in a closet" thing.
I don't care if they kiss in public (well, I had a problem with it once, but that is a bit of a different story), but due to the above-mentioned factors (and some other experiences), I am sometimes a bit reserved towards homosexuals (although I try hard not to, and usually, it works). Nevertheless, I still regularly meet with those friends of mine, and I also tolerate and accept homosexuality in general, and oppose any kind of discrimination.