The survey is at: http://cc.media.mit.edu/p2p/
The ANONYMOUS survey consists of 7 questions, and you can respond to all, some or none of them. The PHP data collection script does not log any identifying information - it simply logs a timestamp and the responses to each of the questions. This survey is approved by MIT's Committee on the Use of Humans as Experimental Subjects (COUHES). Information about confidentiality and other research guidelines can be found at http://web.mit.edu/committees/couhes/procedures_surveys.shtml
Feel free to email me at email@example.com if you have any questions about the survey or the study itself.