Ashton Kutcher — the King of Twitter — has suddenly gone all coy over reports that his entourage is putting the final touches on a deal to have him replace Charlie Sheen on CBS’s “Two and a Half Men.”

“I’m starting to become convinced that people put my name in articles just to improve their SEO [search engine optimization] or hoping I’ll tweet it,” Kutcher tweeted peevishly Thursday night. Poor baby!

His reference is to published reports that he is in talks to take a role on the country’s most popular sitcom, which suddenly found itself one man short when Warner Bros., which produces the show, sacked Sheen back in March. The studio cited his erratic behavior and screeds against show creator Chuck Lorre.

Great. Kutcher’s finally got something he could tweet that we really want to know about, and now he clams up. Geesh!

Later in the evening, Kutcher tweeted: “what’s the square root of 6.25?”

The answer, of course, is 2.5.

Kutcher’s reps are in advanced talks to have him join the comedy in the fall. His is the second name in 48 hours to surface as the designated Sheen replacement. Warner Bros. was also in a state of advanced talks with Hugh Grant to join the show, but that deal fell apart at the 11th hour over “creative differences.”

And by “creative differences,” the trades meant: “Hugh Grant did not want to work that hard.” Because if you’re going to be the star of the country’s most popular comedy series, you’re signing up for 24 episodes a season. That’s 24 whole weeks of work!

The report on Kutcher first broke in the trade publication Broadcasting & Cable. Then the trade publication Hollywood Reporter took that ball and ran with it, noting that Kutcher would be a great get, because he’d bring his youthful fan base to CBS, as well as his 6.7 million Twitter followers, which would help CBS promote the show.

CBS and Warner Bros. got fooled by that gag once before, back in 2009 when CW — ironically a co-venture of CBS and Warner Bros. — bought Kutcher’s semi-autobiographical models-are-more-interesting-than-you drama “The Beautiful Life.” Kutcher was going to use the whole Twitter thing to get all his followers to watch the show and CW would have more viewers than it knew what to do with.

Kutcher did, in fact, tweet the heck out of it, in the days leading up to, and after, its launch. The ratings were so spectacularly lousy, CW killed “The Beautiful Life” after just two episodes — and that’s saying something because, remember, we’re talking CW here.

Anyway, Warner Bros. issued a terse “no comment” Thursday on the Kutcher report. CBS is scheduled to unveil its new prime-time plans — and, presumably, its Sheen replacement plans — on Wednesday at Carnegie Hall.

Couric producer to ABC

Katie Couric has not yet said where she’s going to land when she leaves “CBS Evening News,” but her departing executive producer, Rick Kaplan, has already landed at ABC News, where he will executive-produce “This Week With Christiane Amanpour.”

Kaplan will also oversee ABC News’s political coverage, ABC News President Ben Sherwood announced Thursday.

“His mission: to lead ‘This Week’ to #1 and to guide ABC News to dominance in the 2012 elections and beyond,” Sherwood said in a memo issued Thursday — which is also Kaplan’s last day at CBS News.

Kaplan will have his work cut out for him. Last Sunday, “This Week” finished a distant third among the 25-to-54-year-olds who are the ad-sales bread and butter for news programming. “This Week” averaged 755,000 viewers in that age bracket, to “Face the Nation’s” 913,000 on CBS and “Meet the Press’s” 1.11 million on NBC.

That said, Amanpour’s show was up 11 percent in that age bracket compared with the program’s year-ago performance. Last Sunday’s show featured national security adviser Tom Donilon, former secretary of state (and ex-Jack Donaghy gal-pal) Condoleezza Rice and Pakistan’s ambassador to the United States, Husain Haqqani.

Ian Cameron, the ABC News executive producer who helmed “This Week’s” relaunch when Amanpour became host, left the show at the end of 2010.

Although Kaplan started at CBS in the ’70s, his latest appointment is a homecoming of sorts: He spent about 20 years at ABC as executive producer of “Good Morning America,” “Nightline,” “PrimeTime Live” and “World News Tonight With Peter Jennings.”

Kaplan really gets around. Over the course of 40 years in news, he’s worked at four major networks and served as president of two cable news operations, MSNBC and CNN.

Sherwood has known Kaplan since the summer of ’89, when Sherwood joined ABC News as an associate producer at “PrimeTime Live.”

“Screening pieces with Rick still evokes the most vivid, visceral memories. We all learned so much from Rick about storytelling, showmanship and the fighting spirit,” Sherwood said, adding:

“Welcome home, Rick. It’s great to have you back.”

‘The Voice’ expands

Encouraged by the show’s early ratings, NBC has decided to expand the live episodes of its singing competition series “The Voice” to two hours — from 9 to 11 p.m. They will follow original episodes of the network’s other performance-competition series, “America’s Got Talent,” which will air at 8.

After the “battle” rounds of “The Voice” — now airing Tuesdays (10 to 11 p.m.) through May 31 — the series will broadcast live two-hour episodes on Tuesdays from June 7 through June 28.

“America’s Got Talent” will debut May 31 as previously scheduled, but from 8 to 10 p.m. It will continue on Tuesdays; beginning June 7, it will air from 8 to 9 p.m. (Also: Starting June 1, the second night of “America’s Got Talent” will air from 9 to 10 p.m.)

In its first three weeks on the air, “The Voice” has averaged nearly 12 million viewers and 5.3 percent of the country’s 18-to-49-year-olds. That makes it the No. 1-ranked new series of the season in that age bracket and the No. 3 entertainment series overall, behind only Fox’s two editions of “American Idol.”