Message from the General Chairs On behalf of the International World Wide Web Conference Committee (IW3C2) and Beihang University, we are delighted to welcome you to the 17th International World Wide Web Conference (WWW2008) in the historical city of Beijing, the capital of China and the host of the 2008 Olympics Games. The WWW conference is the premier international forum for sharing the latest information about the Web, its technologies, and its future evolution. The theme of this year's conference is "One World, One Web" with three daily themes that reflect the three major trends of the Web: Web of People: People are moving from passively browsing the Web to actively collaborating and sharing their lives on the Web. Web of Rich Media: The Web is moving from presenting plain text and simple images to providing rich media experiences, and Web of Devices: Access to the Web is becoming ubiquitous as it now comes from computers, TV's, mobile phones, and various devices. WWW2008 received a record number of refereed paper submissions this year. Complementing the high quality papers are 12 exciting workshops, 15 informative tutorials, several expert panels, Industrial track and more than 110 posters with late-breaking results, plus the always-popular Developers Track, W3C track, and a special WWW in China track. You certainly have a very busy week ahead of you. It is difficult to estimate the time and effort required to organize a conference of this magnitude - and we could not have done it without the passion and dedication from many people on the WWW2008 team. Particularly demanding is the task of the Program Chairs: we thank Wei-Ying Ma, Andrew Tomkins, and Xiaodong Zhang for their many hours of work on the conference, and to Yahoo! for hosting the PC meeting in California. The high quality of the technical program owes much to the efforts of the PC chairs, as well as those of the track chairs, deputy chairs, program committee, and external reviewers. Zaiqing Nie, our proceedings chair, did an excellent job in assembling the final proceedings with the help from Lisa Tolles of Sheridan Printing to meet the ACM requirements. The Local Organizing Committee did a remarkable job in meeting the demands of a large International Conference like WWW2008. Beihang Asset Management Co., Ltd served as the conference PCO, dealing with many logistical issues. Key20 Media handled the WWW2008 sponsorship program. We thank Yammie Yuen for her super-human efforts as Registration Chair, Financial officer, and Web master! IW3C2 and WWW2007 (especially Carey Williamson) gave valuable advice and support at crucial moments. Anqi Li from our PCO handled the hotel contracts, travel information, social events, exhibitions, and CD production. Lily Zhang did an excellent job handling the publicity of the conference. Hailong Sun worked diligently on the program guide and Student Travel Assistance program. The WWW2007 volunteer team coordinated by Chunming Hu, Zongxia Du, and John Miller did thorough preparations to ensure that everything would run smoothly during the conference week. Special thanks go to our two General Vice Chairs: Hsiao-Wuen Hon, managing director of Microsoft Research Asia, who oversaw our marketing efforts and provided many excellent resources from MSRA, and Professor Yunhao Liu from HKUST, who oversaw the conference operations. We also wish to thank our four plenary speakers (Tim Berners-Lee, Kai-Fu Lee, Harry Shum, and David Belanger) for sharing their insights, as well as the other authors and presenters for their contributions. We also thank our sponsors (especially Microsoft and Google) for their generous financial contributions to the conference. Thank you all for attending WWW2008. Enjoy the conference, the food, and the beautiful and charming city of Beijing! Jinpeng Huai Beihang University Robin Chen AT&T Labs iii