We present a conceptual framework for location-aware community systems and results from two studies of how socially-defined places influence people's information sharing and communication needs. The first study identified a relationship between people's familiarity with a place and their desire for either stable or dynamic place-related information. The second study explored the utility of various system features highlighted by our conceptual framework. It clarified the role of place information in informal social interaction; it also showed that people valued, and were willing to provide information such as ratings, comments, and event records relevant to a place. These preliminary findings have important implications for the design of location-aware community systems. In particular, they suggest that such systems must integrate information about places with data about users' personal routines and social relationships.