Did Beyonce lip the first half of DIL at the Grammys? Coz girl not even the best sound system can make a singer sounds so flawfree. The later half was a little crude and messy so I'm sure it was really her singing.
Being objective, it sounded fully lip-synced (her voice was SO crystal clear and the way she was miming just didn't feel right, also the bit where she semi-slipped)
until Jay-Z showed on stage, then she was singing live.
Katy is not really a threat to anybody. Her oblivion is inevitable in the coming years. She can't keep releasing disney tunes til she's 35. she's now 30