I did see this news elsewhere and seeing this thread, I decided to put into words the first opinion ive had on Buffy in a long while.
So what follows is my opinion.
You know who I feel bad for all of this, Gunn. If there was ever a guy who earnt the mentle of Slayer its Gunn, of course the Buffy verse was very different then, when the idea of 1 slayer still meant something (ok Faith and Kendra had both been seen, but this was along time before "every girl who could be a slayer, becomes a slayer" )
As there is no longer a "The Slayer" no chosen one, that will of course change things, but Gunn was killing vampires long before this, so really thats not important either. Billy will earn the mantle of slayer, but only in the eyes of Buffy, but the mantle is meaningless really Gunn was killing vampires without need Buffys respect.
So before I move on, a quick round up, the title "Slayer" does not mean what it used to, men have always been able to slay vampires, its also not something Buffy gets to decide.
What troubles me with this move, is really what troubled me with Buffys final episode, the idea of an army of slayers is nice, but in reality it would not end up like that. All it would create is young women with the urge to get into a fights, Buffy would not meet yet alone train the majority of them, which would most likely mean some vampire gets an easy slayer kill, or the woman, gets into one too many fights, and without the proper training gets beat, killed, or gets down a self destructive path landing her in jail or worse.
In Billys example we see the ill advised message that femininity means great fighting strength, a highly questionable message to send to anyone. You also have this idea that gay men, are feminine and the suggestion that deep down they just want to hang with the girls etc, which maybe true in some cases, but is an over used cliché in the media.
You could go as far as to say that gay men having to prove there femininity to some alpha female, to be accepted is backwards, and just as bad as more traditional forms of homophobia.
So backtracking to earlier in my post, now the slayer title is meaningless, and so many girls can be a slayer, obviously Buffy needs to train them to a certain level, before she sees there training as complete and them as fully disciplined slayers, capable of all those other things slayers need to do, more than just kicking and punching really hard, something of course that mirrored her early training, or for that matter any fighters training. If someone without the slayer magic, can pass that training, why not call them a slayer, be they, male, female, Klingon or Silurian
So in conclusion, I dont see the big fuss Buffy fandom is making, and far from empowering gay men, it may continue to stereotype them. I think an straight male slayer, one who actually is a slayer, would have been far more interesting.