GAY is the new straight.


Gay marriage may not be the law of the land, but it has become a cornerstone of network television. NBC calls its new comedy about a homosexual couple adopting a baby “The New Normal,” and that kind of understates it. There is nothing particularly new about gay characters on sitcoms. This season they are not only normal, they seem de rigueur.


Several new shows have gays in secondary roles, including “Emily Owens, M.D.,” a new medical drama on CW. Mamie Gummer plays an insecure intern who has a lesbian friend at the hospital. But that “some of my best friends are gay” scenario has been around for years. Nowadays it’s almost harder to find a series, scripted or reality, that doesn’t have a gay character.


Gay leads aren’t new, either, but they are more rare. Or were. “The New Normal” takes the ABC show “Modern Family” a step further by focusing on one gay couple. “Partners,” on CBS, splits the difference with architects — one straight, one gay — who are best friends, a show made by the creators of “Will & Grace.”


It sounds perverse, but some of the most unconventional comedies this fall aren’t about sexual orientation. The sitcoms that try to stake new ground are vintage, refashioning shows from 1960s and ’70s.


The weirdest is “The Neighbors” on ABC, about an average family that moves into a suburban enclave with odd but friendly aliens — “My Favorite Martian” with a touch of the Coneheads.


NBC is also trying to repackage group therapy, which seemed a little old hat even in the days of “The Bob Newhart Show.” In “Go On” Matthew Perry stars as a sports radio talk-show host forced by his bosses to attend a support group after his wife dies. (In fairness, this show is also influenced by “Community.”)


“The Mindy Project” on Fox is about a single doctor with a “Rhoda”-like craving to find a mate. “Ben and Kate,” also on Fox, isn’t about a same-sex marriage, a mixed-race marriage or a saucy love-hate work relationship. It’s about a brother and sister — Buffy and Jody all grown up in a new kind of “Family Affair.”


Most of these shows aren’t as good as “The New Normal,” which has wit and charm, but they seem, oddly enough, more surprising. And that’s the problem with joining the mainstream — it’s so much harder for a comedy to stand out from shows that seem a lot like the show next door.


“Partners” is by Max Mutchnick and David Kohan of “Will & Grace,” and the Bette Midler jokes and double-entendres that made that NBC sitcom so original and naughty in 1998 are now so familiar that they can seem like clichés.


Michael Urie (“Ugly Betty”) plays an uninhibited gay architect, Louis, who is best friends and business partners with Joe (David Krumholtz, “Numb3rs”), a straight architect who is also a straight arrow. Like Jack on “Will & Grace,” Louis is an endearingly narcissistic free spirit who loves fashion and home décor, and says things like, “Anyone who wears Cosmic Radiance by Britney Spears should not serve on a jury.”


Stereotypes are often true but only truly funny when they seem freshly revealed. Shows like “Ugly Betty,” “Glee” and “Modern Family” have lovingly, and exhaustively, sent up every classic gay trait. That could be why the ABC comedy “Happy Endings,” which willfully resists the most obvious caricatures, will begin its third season in October and is still very funny.


The gay friend in that group is moody, often depressed, smart, slovenly and slightly overweight with no interest in shoes, handbags or pop divas. It’s the straight men on “Happy Endings” who have so-called effeminate interests: The married yuppie loves facials and shopping; the straight single guy is so vain about his style sense that his friends have to intervene to make him stop wearing V-neck T-shirts.


So the bar is raised very high for “The New Normal.” The show’s creators include Ryan Murphy, who is known for “Glee” and “Nip/Tuck” and was already facing high expectations. The pilot meets most expectations, a tribute to the writing and also to one of the stars, Andrew Rannells. That actor was a hit in the Broadway musical “The Book of Mormon” and is just as elastic and delightful in “The New Normal,” even though his character, Bryan, doesn’t stray far from the usual. (His ring tone is Cher singing “Believe.”)