Even though Usher has ducked into a soundstage to start work on his new Babyface-produced film project, "Light It Up," the R&B singer remains all over the airwaves.Aside from his newest single, "One Day You'll Be Mine," Usher also turns up on Cam'ron's "Feels Good," which he says was inspired by the Teddy Pendergrass tune, "Loving Somebody." Usher told the MTV Radio Network that they had a great time collaborating together, and during the sessions, the Harlem-based Cam'ron also introduced Usher to the rest of a new group who are also producer Jermaine Durpri's newest signings to his So So Def Label. "Cam was hot," Usher explained, "he was really cool, and he showed me all about 'Harlem World." As we previously reported (see "Mase Group Inks Deal With Dupri"), Harlem World features several extended members of Mase's rap family -- including Cam'ron and Mase's sister, among others. No word yet on whether Cam'ron and Usher will hook up for a video for "Feels Good," but we'll keep you posted.