you should check out the xanga site, and read their "privacy policy"
http://help.xanga.com/about/privacypolicy.htm
"Every time you visit a page on the Internet, your web browser sends specific information to the web site you are visiting. Xanga's server logs automatically collect and store this information from your web browser, including your IP address, specific type of browser software, Xanga-related cookies (see below), and the pages you visit at Xanga."