Warner Brothers has filed a brief in its lawsuit against file-locker service Hotfile in which it admits that it sent copyright takedown notices asserting it had good faith to believe that the files named infringed its copyrights, despite the fact that it had never downloaded the files to check, and that it sometimes named files that were not under Warners's copyright, including files that were perfectly legal. Among the files that Warner asked Hotfile to remove was a file called "http://hotfile.com/contacts.html and give them the details of where the link was posted and the link and they will deal to the @sshole who posted the fake" and others.
The studio also "admits that it did not (and did not need to) download every file it believed to be infringing prior to submitting the file's URL" to the Hotfile takedown tool. That's because "given the volume and pace of new infringements on Hotfile, Warner could not practically download and view the contents of each file prior to requesting that it be taken down."
This is interesting because the DMCA requires a copyright holder issuing a takedown notice to state that it has a "good faith belief that the use of the material in the manner complained of is not authorized by the copyright owner, its agent, or the law." It's hard to see how anyone at Warner Brothers could have formed any beliefs—good faith or otherwise—about files it admits that no human being at Warner had even looked at.
The recently-proposed Stop Online Piracy Act, which is backed by the major Hollywood studios, would give copyright holders new powers to cut off websites' access to payment processors and advertising networks. It even includes a new DMCA-style notice-and-takedown scheme. But given the cavalier way that Warner Brothers has used the powers it already has under the DMCA, policymakers may be reluctant to expand those powers even further.