Gay is apparently the new black for comics superheroes as rival publishers Marvel and DC duke it out over who's got the best pink credentials.

First off this week, the Daily Mail got its knickers – worn outside of its trousers, presumably – in a twist over the possibility that one of the superheroes in the DC universe inhabited by Superman, Green Lantern and Wonder Woman is going to be unveiled as gay.

Then, yesterday, Marvel shipped editions of its Astonishing X-Men #50 a day early to comic shops so fans could read about Northstar – mainstream comics' first openly gay character – asking his partner to marry him.

But it's the two-fisted heroes of DC who have the Mail in a kerfuffle, and the paper even goes as far as to point the finger (without a shred of evidence) at the Dark Knight himself – possibly DC's most masculine character, ever. While it's – rightfully – unlikely that any jury these days would accept accusations of homosexuality as defamatory (as they did in the case of Jason Donovan v The Face magazine in 1992), by the same token the goddamn Batman has spare vials of testosterone in his utility belt, just in case his outrageously high levels dip, right next to the shark repellent (not really).

"Is Batman gay?" shrieks the Mail, deftly ignoring the more mature-audience-targeted versions of the character that have graced movie screens and comic books in recent years, in favour of illustrating the story with a shot from the kids' cartoon Justice League. Who knows? Not the Mail, which says only that DC co-publisher Dan DiDio revealed at the weekend's London comic convention, Kapow, that "an existing character – who was previously assumed to be straight – will become 'one of our most prominent gay characters'."

But the Bat-family has form for this sort of thing, the Mail – almost sadly – acknowledges in its closing paragraph: "Batwoman, a DC favourite, made her comic book comeback as a lesbian in 2006."

The Mail has sourced the story from Bleedingcool.com, of course; the go-to site for comics news, which presented the news in a very measured, non-judgmental way, and has a lovely update at the end of the original piece (which went live on Sunday) thanking mainstream news organisations for linking to their site and offering a potted history of gay comics' characters "for the files", which is worth reproducing here:

"Image Comics and Wildstorm published comics in the noughties featuring gay couple Midnighter and Apollo, based on Batman and Superman, something that was played down and censored when DC bought Wildstorm, though eventually the pair were allowed to marry in the comics, in a ceremony conducted by a fictitious version of Ellen DeGeneres. Of late, both Marvel and DC have significantly increased the number of LGBT [lesbian, gay, bisexual, and transgender]" characters, prominently in books such as Young Avengers, Batwoman, 52, Astonishing X-Men and X-Factor, Marvel's first kiss between male superhero characters."

Goodness knows how many superheroes there are in the DC universe these days, but with one recent study putting the proportion of gay people in the US at 1.7% of the population, then it stands to reason there would be easily enough LGBT characters to form their own superteam, should they wish to.

Perhaps it's because comics are still considered juvenile reading matter in some quarters that the Mail feels the need to ponder whether Batman is gay, but it's like it's never heard of Frederic Wertham, the psychologist whose 1950s book Seduction of the Innocent prompted Nazi-style comic burnings by petrified parents after its observations along the line of: "Only someone ignorant of the fundamentals of psychiatry and of the psychopathology of sex can fail to realise a subtle atmosphere of homoeroticism which pervades the adventures of the mature Batman and his young friend Robin."

Whoever DC decides will earn the honour of being its most high-profile gay character remains to be seen, but it would have a certain symmetry if the Mail was dead right and – half a century after Wertham tried to get Batman banned for his homoerotic overtones – the Dark Knight did indeed come out of the bat-closet.