Couric, whose "All Access Grammy Special" airs tonight (9:00-10:00 PM, ET/PT) on CBS gets the Grammy nominees to open up before the big show.
"We have an all-star lineup of the top performers in American music. Carrie Underwood, Taylor Swift, Metallica, Ne-Yo, The Jonas Brothers and Justin Timberlake," Couric told Early Show co-anchor Harry Smith.
"You look 'slamming,' as the kids are saying," Timberlake said to Couric during the special.
"Justin Timberlake is known for his hits, but did you know he's ranked No. 15 among famous musician golfers? Now, that's an achievement!" Couric said.
With six Grammys under his belt, Timberlake is nominated for "Best Pop Collaboration with Vocals" this year for his performance on Madonna's hit, "4 Minutes."
"Was it hard to click with Madonna at first?" Couric asked.
"I don't know that it was hard. It's crazy to me that I get paid to tell these people my opinions," Timberlake admitted.
"Were you intimidated by her at all?" Couric inquired.
"No, no, she's short. So I wasn't afraid at all," Timberlake joked.
"What sorts of things inspire you now?"
"I mean, I'm constantly inspired by anybody who just doesn't care about what's going on. Who says, 'Well, I'm going to take a left turn here,'" Timberlake replied.
Like millions of others, Timberlake told Couric he's a fan of Lil 'Wayne.
"I love Li'l Wayne," Timberlake said. "Wayne strikes me as somebody who is enjoying it. When I heard you were doing a Grammy special, I was like 'I want to see Katie and Lil' Wayne in the same frame!" ' Timberlake said.
Couric even had a chance to go bowling with rapper Li'l Wayne, who's up for eight Grammys.
"I'm a gangster Miss Katie," Lil'Wayne told Couric during the special.
"What does that mean, when you say, 'I'm a gangster?'" Couric asked.
"I don't take nothing from no one," Lil Wayne said.
According to Couric, this tough-talking rapper insists what you see is not necessarily what you get.
"Can you take me on a little journey through your face?" Couric asked, referring to Lil' Wayne's tattoos.
"Okay. I have 'misunderstood' on my face, because I do feel that a lot of times, I am very misunderstood," he said.
His album, "The Carter III," has sold nearly 3 million copies, making it the No. 1-selling album of 2008.
"How would you describe the typical Li'l Wayne fan?" Couric asked.
"I can't. Because I've seen everybody," he responded.
"Why do you think your music is really sort of hitting the stride?" Couric asked.
"I work very, very hard, Miss Katie. And hard work pays off. If you work that hard, you're going to get good and good turns to great and hopefully I'm the definition of that," Lil Wayne said.
"Do you think you're great?" Couric asked.
"I do," Lil' Wayne conceded.
The young rapper and New Orleans native has more Grammy nominations than any other artist, Couric pointed out.
"What was it like to golf with Justin Timberlake?" Smith asked.
"It was so much fun. First of all, he's an extraordinarily nice guy, and he's very smart and savvy. He's not only -- he golfs, but he also does music, he produces, he sings, he's got his own fashion line, he acts. He does comedy sketches, as we know from some of those famous 'SNL' skits. He's really into everything, but an unbelievably nice guy," Couric said.
"All right, Miss Katie, we're into you! Thank you for stopping by this morning!," Smith kidded.
"Thank you, Mr. Harry. It was funny to hear Li'l Wayne say 'Miss Katie, I'm a gangster.' I have never heard those two things together. He was terrific, too. Very, very smart. A straight-A student in high school, by the way," Couric said.
Couric's "All Access Grammy Special" airs tonight at 9/8 central on CBS.
The 51st Annual Grammy Awards will be broadcast live from The Staples Center in Los Angeles Sunday (8:00-11:30 PM ET/delayed PT), also on CBS.