The rapid advent of “Web 2.0” applications has unleashed new HTTP traffic patterns which differ from the conventional HTTP request-response model. In particular, asynchronous pre-fetching of data in order to provide a smooth web browsing experience and richer HTTP payloads (e.g., Javascript libraries) of Web 2.0 applications induce larger, heavier, and more bursty traffic on the underlying networks. We present a traffic study of several Web 2.0 applications including Google Maps, modern web-email, and social networking web sites, and compare their traffic characteristics with the ambient HTTP traffic. We highlight the key differences between Web 2.0 traffic and all HTTP traffic through statistical analysis. As such our work elucidates the changing face of one of the most popular application on the Internet: The World Wide Web.