Future wireless IP networks will scale to millions of heterogeneous terminals and provide seamless and ubiquitous content services. However, wireless networks and terminals have drastically different characteristics than their wireline counterparts in terms of bandwidth availability, mobility, processing/display limitation and power consumption requirements, and some key assumptions that existing wireline web protocols and applications rely on become invalid in wireless environment. To achieve adequate user experience and high quality of service, novel mobile content distribution techniques overcoming these difficulties must be developed. In this paper, we develop taxonomy of content distribution techniques that consists of network scaling, endpoint acceleration and protocol and content optimization. We review existing wireline content distribution techniques that will be useful in wireless networks using this framework. We further identify key challenges that mobile content distribution must address in developing scalable, ubiquitous and context-aware mobile content services.