<b>Photos:</b> Katy Perry at the Grammy Nominations Concert

Singer Katy Perry performs at Club Nokia.   (Kevin Winter/Getty Images)

Singer Katy Perry performs onstage.   (Kevin Winter/Getty Images)

Singer Katy Perry performs.  (Kevin Winter/Getty Images)

Singer Katy Perry performs at the Grammy Nominations Concert Live!  (Kevin Winter/Getty Images)

Singer Katy Perry performs onstage at the Grammy Nominations Concert Live! at the Club Nokia.   (Kevin Winter/Getty Images)

Singer Katy Perry performs during the concert.  (Kevin Winter/Getty Images)

Singer Katy Perry performs in Los Angeles.  (Kevin Winter/Getty Images)

Singer Katy Perry performs at the Grammy Nominations Concert Live!  (Kevin Winter/Getty Images)

Singer Katy Perry performs.   (Kevin Winter/Getty Images)

Singer Katy Perry performs.   (Kevin Winter/Getty Images)

Singer Katy Perry performs onstage.   (Kevin Winter/Getty Images)

Singer Katy Perry performs onstage.   (Kevin Winter/Getty Images)

Singer Katy Perry performs at the Grammy Nominations Concert Live! at the Club Nokia.   (Kevin Winter/Getty Images)

Singer Katy Perry performs onstage.   (Kevin Winter/Getty Images)

Singer Katy Perry performs at the show.   (Kevin Winter/Getty Images)

Singer Katy Perry performs onstage at the concert.   (Kevin Winter/Getty Images)

Singer Katy Perry performs during the Grammy Nominations Concert.   (Matt Sayles/AP)

Singer Katy Perry performs during the Grammy Nominations Concert.   (Matt Sayles/AP)

Singer Katy Perry performs during the Grammy Nominations Concert.   (Matt Sayles/AP)

Singer Katy Perry performs during the Grammy Nominations Concert.   (Matt Sayles/AP)

Singer Katy Perry performs during the Grammy Nominations Concert.  (Matt Sayles/AP)

Singer Katy Perry performs during the Grammy Nominations Concert.   (Matt Sayles/AP)

Pop music star Katy Perry performs during a rehearsal.   (Robyn Beck/AFP/Getty Images)

Pop singer Katy Perry sings during a taped rehearsal for the Grammy nominations TV special.  (David McNew/Reuters)

Pop singer Katy Perry sings during a taped rehearsal for the Grammy nominations television special in Los Angeles.  (David McNew/Reuters)

Pop singer Katy Perry sings during a taped rehearsal for the Grammy nominations television special.  (David McNew/Reuters)

Pop singer Katy Perry sings during a taped rehearsal for the Grammy nominations television special.   (David McNew/Reuters)

Pop singer Katy Perry sings during a taped rehearsal for the Grammy nominations television special.   (David McNew/Reuters)

Pop singer Katy Perry sings during a taped rehearsal for the Grammy nominations television special.   (David McNew/Reuters)

Pop singer Katy Perry sings during a taped rehearsal for the Grammy nominations television special.   (David McNew/Reuters)

Pop singer Katy Perry sings during a taped rehearsal for the Grammy nominations television special.   (David McNew/Reuters)

Pop singer Katy Perry sings during a taped rehearsal.   (David McNew/Reuters)

Pop singer Katy Perry sings during a taped rehearsal for the Grammy nominations television special.   (David McNew/Reuters)

Pop singer Katy Perry sings during a taped rehearsal for the Grammy nominations television special.   (David McNew/Reuters)

Pop singer Katy Perry sings during a taped rehearsal for the Grammy nominations television special in Los Angles.   (David McNew/Reuters)

Pop singer Katy Perry pauses during a taped rehearsal for the Grammy nominations television special.   (David McNew/Reuters)

Pop music star Katy Perry performs during a rehearsal for the Grammy Nominations Concert.  (Robyn Beck/AFP/Getty Images)

Pop music star Katy Perry performs during a rehearsal for the Grammy Nominations Concert.   (Robyn Beck/AFP/Getty Images)

Pop music star Katy Perry performs during a rehearsal for the Grammy Nominations Concert.   (Robyn Beck/AFP/Getty Images)

Pop music star Katy Perry performs during a rehearsal.   (Robyn Beck/AFP/Getty Images)

Pop music star Katy Perry performs during a rehearsal for the Grammy Nominations Concert.   (Robyn Beck/AFP/Getty Images)

Pop music star Katy Perry performs during a rehearsal.   (Robyn Beck/AFP/Getty Images)

Pop music star Katy Perry performs during a rehearsal for the Grammy Nominations Concert.   (Robyn Beck/AFP/Getty Images)

Pop music star Katy Perry performs during a rehearsal for the Grammy Nominations Concert.   (Robyn Beck/AFP/Getty Images)

Pop music star Katy Perry performs during a rehearsal for the Grammy Nominations Concert.   (Robyn Beck/AFP/Getty Images)

Pop music star Katy Perry performs during a rehearsal.   (Robyn Beck/AFP/Getty Images)