The Ninth Circuit held last week (in McNeil v. Verisign, Inc.
) that ICANN isn't a state actor and therefore isn't required to respect free speech or due process rights under the U.S. Constitution. (For general background, see these law review symposium issues: 6 J. Small & Emerging Bus. L. no. 1 (Spring 2002)
15 J. Marshall J. Computer & Info. L. no. 3 (Spring 1997)
UPDATE: Eric Goldman lists previous decisions declining to find state action by private Internet entities here.