One of the premier resources for expats moving to China, eChinacities has it all: city-specific write-ups, major events, directories, and a massive database of articles on every possible topic related to living in China.
Article topics range widely: find useful articles on updated visa regulations and finding the correct visa application category to suit your circumstances; info on buying good air purifiers; making sense of rumours for travel during Golden Week; sex education in Chinese schools; Western recipes utilizing the limited resources in Chinese kitchens and supermarkets; street food and food safety; Chinese film; travel advice, and so forth.
Compiled by a number of locals and expats from across the country, the city guides are also useful introductions to the major metropolitan centers in China, providing details on the main tourist attractions, events, and news.
The Weird China News section is an interesting read and as the name suggests gives some pretty funny accounts of what is happening in the PRC.
The Answers section is a good place to have any questions answered in a variety of categories, including visas, law, safety, online censorship, money/banking, transportation, family, business, travel, and culture. The forums are also very active and have job postings from around the country as well as lots of Sino-centric debate and discussion.