Xintiandi is basically the Harrods of Shanghai; great if it is to your taste. If not, give it a miss. One certain plus for Xintiandi is a mall with a large screen cinema showing movies in English on the back side of the complex.
I moved here last year, since i know Xintiandi, I go there shopping or having dinner at least 3 times a month, even just hang around Xintiandi will always be my first chioce.
Node