Well, actually the literature about the samurai is very full of depictions of "man on man" mostly of a bi-sexual kind, since samurai did take on female wives, lovers, and had children. That is not to mean that some of these men were not homosexual, but just that only being homosexual was not the thrust of the taking of men. It was seen as a "pure form" of love, from a warriors perspective.
"Love thy brother.."
This was also the case for ages in Europe many centuries ago. Or at least before Christianity took root. (see: "Spartans"
http://forums.bungie.org/story/storyarchive.pl?read=5119)
[quote]If this was common among samurai and widely accepted, wouldn't we see it being acted out in most of the samurai movies? [/quote]
Films of this sort are not popular as far as homosexuality is concerned, since we are talking about film making in the modern era. Samurai movies are just the same as Westerns are seen in the US, as action, violence, and morality plays.
http://www.glbtq.com/arts/japan_film.html
By the way, although effeminate behavior by men is not really harped on, doesn't mean that homosexuality is acceptible in Japan. It isn't. Homosexuals are very much in the closet there and it is not common for someone to "come out". If they do, it is seen as tragic, and disgraceful for, parents, friends, and more importantly there for work. Having a gay "salary man" or business man around is not very acceptable at all. Japan is still very much a male heterosexual dominated society/culture and that includes discrimination based on sex/sexual orientation.
That said, you will find a few comedians and entertainers "on TV" and in "gay bars" which are quite popular there. So, you could say that in Japan it is now only okay to be "gay" if you are in the entertainment (clowning) business.
I am not gay, so maybe someone may correct me if they find this information and my perspective to be wrong.