Both my friends charge their MBPs in China without having to buy an adapter or transformer. They use 220V. However, the sockets/surge protectors in China are crap. Personally, I've had a laptop charger and an iP4 charger get fried from plugging it into a socket in China. My friend's Dell laptop charger also got fried eventually. She also says that her MBP's charger was temporarily disabled (wouldn't charge even though electricity was still running) for a few hours after a technician outside her hotel room was fiddling with the breakers. She was using a China-bought surge protector.
When I go back in September, I'm definitely not plugging in my new MBP11 into the Chinese sockets for sure. I'll probably bring a heavy duty transformer and a USA surge protector if that's compatible. I still need to research this myself a little bit. Hope my experiences in Beijing helps you decide what you should do.
