I think if we take the moral aspect, or what is perceived as "normal", then that's in the eye of the beholder.
If the subject is "natural", now we are into science, structure/function relationships, reproduction, etc. I think the bulk of that goes against the "homosexuality is natural" side, but they have their points.
To me, the real issue is more practical - is it healthy and good? I dont know what the exact numbers are now, but back in grad school I remember the average lifespan of a white gay male was 42 - 30 some years shorter than white heterosexual males. That low number is mostly due to higher rates of suicide and accidental death among younger gay males. Back then, we were also at the height of the AIDS epidemic.
However, there are several other important things to note about this particular group. They are the most sexually promiscuous segment of society. One prof, an MD who worked in an STD clinic, said that it was not uncommon for one of his patients to report 2000+ sexual partners that included very reckless behavior like anonymous sex. There are other tendencies toward other risky behaviors.
You package all of that together and being a gay male poses some very serious threats to health and life - in the macro and across the board. But the question is does that arise from simply being a gay male or is it because of external factors like loss of family relationships and social approval due to a lack of acceptance, among other things.
So, people can find reasons to land anywhere on the continuum between celebration and condemnation.
