MARIAH SWITCH ENRAGES NBC

Hell hath no fury like a network scorned.

Music-industry insiders and network sources say NBC is furious with Mariah Carey, her manager Benny Medina and her reps at Def Jam, because they promised Carey would perform on "Today" to promote her new album, "E=MC2" — but instead she's going on arch-rival ABC's "Good Morning America."