Rumor Sites Looking to Block Subpoenas reports that lawyers representing previously subpoenaed websites have challenged those subpoenas under First Amendment protection:

The subpoenas should not be permitted because Internet journalists deserve the full protection of the First Amendment that their traditional brethren have long enjoyed, the lawyers said in a brief filed in Santa Clara Superior Court.

As noted in the article, the issue raises the question of whether internet website publishes enjoy the same protection as traditional journalists.