Katy Perry's twofold obligation: Victoria's Secret, Grammy Concert: While Katy Perry was shown performing on last night's Victoria's Secret Fashion Show, the pop star was busy rehearsing for the Grammy Nominations Concert Live! at the Club Nokia in L.A. You can watch the Grammy nominations concert tonight at 10 p.m. (live for the East Coast/tape-delayed for West Coast) on CBS. This is the third year nominations are being announced on the live concert show.

LL Cool J will be the host of the one-hour special, and performers along with Perry will include Justin Bieber, Train, Miranda Lambert, B.o.B and Bruno Mars. Selena Gomez, Dave Grohl, Hayley Williams and Stevie Wonder are among the presenters slated to appear.