Everyone has heard of Shanghai as the culture/fashion, commerce center of China.
You can find almost everything in Shanghai, and there is always something happening.
There is also a good amount of foreigners and you can basically get by with just English.
It is still China with many differences but there is more of a modern western feel to the city. In Shanghai the Chinese will not give you as much special treatment, as they are more used to foreigners.
This can be a good and also a bad point depending on what you hope to experience.
(Photo of Louise and Jasmine, current MEF teachers, visiting Shanghai)