Last week, YouTube said it would use a new system for identifying copyrighted video clips. This announcement was part of a revenue-sharing deal struck with Warner Music. The companies agreed last week that Warner would receive a cut of any ad revenue generated by its clips.

Given that YouTube receives about 65,000 new videos a day, the sheer number of videos posted means that such a system could only be employed selectively.

In a new "corrected version" of the announcement, YouTube promises only an "automated audio identification technology to help prevent works previously removed from the.

Ooops. The revision is important because it seems to imply that copyright owners will still have to locate offending content and flag it to YouTube each time they wish to have it removed.