Shanghai is Beijing's glamorous new sister. The Huangpu River divides central Shanghai into two parts. On the western bank lies what locals call "Puxi", an area known for having a modern decadence of spruced-up Neoclassical and Art Deco buildings and The Bund. The eastern bank lies Pudong, with a view of skyscrapers that were all built within the past twenty years on previous fields that once belonged to the local farmers. Shanghai is the most glamorous and photographed city in all of mainland China, and has grown into a metropolitan city that has a growing population of ex-pats. The ex-pat community relies on the website Smart Shanghai for all recommendations (dining, bars, hotels, events, etc.). It's a good aggregation that shows you places based on cuisine, tag, or location (i.e., South Bund, Jing'an Temple, etc.).
Culturally, Shanghai is a mecca of palaces along the Bund that erected from the mid-19th century to all the way until the 1930s on profits from Shanghai's extensive ports. Trade revenue was made primarily from silks, porcelain, and opium exportation. There is also the former French Concession, where you can find a number of french speaking residences that have either just set up shop there, or have owned shops there for decades selling croissants and having some of the best tea houses in the city. Xintiandi district is where Shanghai's fashion week is held. It is newly renovated and very western in design and it's ever expanding architecture has grown to attract many international travelers. The West Bund is an area being popularized by the art industry. It's stake it new, but is sticking as more and more private museums become a nice investment place to park your cash, while expanding art into a major thriving market.