According to the BBC:
Wearing a red dress and pigtails, Lin Miaoke charmed a worldwide audience with a rendition of “Ode to the Motherland”.
But the singer was Yang Peiyi, who was not allowed to appear because she is not as "flawless" as nine-year-old Lin...Speaking on Beijing Radio station, musical director Chen Qigang said the organisers needed a girl with both a good image and a good voice.
They faced a dilemma because although Lin was prettier, seven-year-old Yang had the better voice, Mr Chen said.
"After several tests, we decided to put Lin Miaoke on the live picture, while using Yang Peiyi's voice," he told the radio station.
"The reason for this is that we must put our country's interest first," he added.
The message to girls world-wide is clear: No matter what your talents might be, be cute or get out of sight. You know, for your country.
UPDATE: Feministing has picked up this story and rightly makes the point that Yang Peiyi is adorable. She's really cute. So it isn't enough just to be cute and talented - you have to be the state-approved variety of cute. Otherwise, here is a state-approved curtain to hide behind, girls!