In an age when celebrity trumps everything, Donald Trump gets his own “Comedy Central Roast” (9:30 p.m., Comedy Central). Back in the olden days in a place I liked to call Planet Earth, roasts were reserved for revered, or at least feared, comedians. They offered a chance for wise guys known for cruel barbs, like Don Rickles, to be on the receiving end of his colleagues’ vicious wit. Or at least a couple thousand dirty jokes.

Now we live in a world where mere celebrity status obliterates all distinctions. That’s how we get spectacles like Elton John appearing on “Inside the Actors Studio.” The singer/songwriter has many arrows in his quiver. A talent for acting is not among them.

Seth MacFarlane will host the Trump roast. He’s a rather perfect choice for the job, as his “Family Guy” franchise is not so much a comedy, or even a coherent story, but a frantic delivery system for an onslaught of disjointed gags about popular culture. Expect much the same here tonight.

Another sign that the roast has degenerated into mere hype is the fact that the “Roast of Donald Trump” has a PG rating. Time was, no comic worth his or her salty mouth would be associated with anything so mild.

• Speaking of Trump, the star of a recent “Celebrity Apprentice” wraps up the first season of “Joan and Melissa: Joan Knows Best?” (8 p.m., WE).

• At the risk of repeating myself, it has always struck me as a bad sign when a hit show trends toward relentless reliance on guest stars. Just last week, Gwyneth Paltrow returned to “Glee” (7 p.m., Fox). Tonight, Kathy Griffin and Loretta Devine guest star as harsh and opinionated judges at the singing regionals. And as has been widely reported, Griffin has modeled her character on a certain former Alaska governor and TLC reality star.

• Erica and Diana’s attempt to foment a coup against Anna has startling consequences on the season finale of “V” (8 p.m., ABC). Like “Fringe” and “The Event,” this series has gathered some fans but perhaps not enough of them to merit another season. Yet another series that has struggled to break out of cult status in the post-“Lost” environment.

• DVDs available today include the first season of NBC’s “Who Do You Think You Are?” and season one of the 1959 Western “Laramie.”

Tonight’s other highlights

• Marital competition on “No Ordinary Family” (7 p.m., ABC).

• A desert ambush leaves three Marines missing on “NCIS: Los Angeles” (8 p.m., CBS).

• Legal matters and hurt feelings on “Raising Hope” (8 p.m., Fox).

• Hunting and gathering car deals on “Traffic Light” (8:30 p.m., Fox).

• A showdown erupts between Alicia and Glenn on “The Good Wife” (9 p.m., CBS).

• Jabbar resists neatness on “Parenthood” (9 p.m., NBC).

• A graffiti artist finishes his last tag on “Detroit 1-8-7” (9 p.m., ABC).

• Few cut him slack after Lights suffers a setback on “Lights Out” (9 p.m., FX).