IPTV is the next frontier for multimedia information and entertainment over service provider networks. As service providers worldwide consider introducing IPTV in their next-generation networks (NGN), industry standards groups have identified two key approaches to IPTV integration. This paper examines IMS-Integrated and IMS-based IPTV, beginning with a review of work underway within the various standards bodies and concluding with an assessment of key functional aspects of each approach, as well as its impact on IPTV network performance and end user quality of experience (QoE).