Talent shows come and go tonight, and that doesn’t even include the season opener of “Glee,” which focuses on the arrival of new talents to replace recent graduates.

“America’s Got Talent” (7 p.m., NBC) ends its seventh season and crowns a winner. A pleasant summer distraction, this season’s “Talent” will likely be best remembered as the moment Howard Stern became more of a mentor than a satirist and a bad boy. Some thought the raunchy radio host might add a little scandal and sizzle to the proceedings, but “Talent” appears to have domesticated the King of All Media. TV talent shows have ways of bringing out the Howie Mandel in all of us.

And speaking of comings and goings, this season will be judge Sharon Osbourne’s last. Her encouraging den mother role will be difficult to replace.

So, with two hours to go, three questions remain: Who will win “America’s Got Talent”? Will he or she become a genuine pop star or merely settle for fleeting celebrity, like most winners of “America’s Next Top Model”? And how will a second episode of “The X Factor” (7 p.m., Fox) affect the ratings for the “Talent” finale?

• Questions also surround “Glee” (8 p.m., Fox) as it enters its fourth season. Will viewers embrace a new batch of musical theater brats? Early on, the high school is abuzz with word of competition to be “the new Rachel,” the new star of the glee club that has been propelled into popularity after winning Nationals. Is “Glee” still “Glee” if the kids aren’t social outcasts?

The season opener takes a whole 10 minutes for the kids to burst into song, an impromptu arrangement of “Call Me Maybe” that they arrange behind Mr. Schuester’s back to determine the new group’s lead soloist. They perform seamlessly, without a false step or false note ­– precisely the brand of musical theater fantasy that makes “Glee” so irresistible — to some.

Tonight’s other highlights

• The network that brought us “I Was Impaled” repeats “I’m Pregnant and … A Nudist” (7 p.m., Discovery Fitness and Health).

• “Great Performances” (8 p.m., PBS, check local listings) presents Richard Wagner’s “Siegfried.”

• New socialites and social climbers arrive on “The Real Housewives of Miami” (8 p.m., Bravo).

• Louie embarks on a mission on “Louie” (9:30 p.m., FX).