From the WSJ (no public link):
A group of major media companies has accused Internet giant Google Inc. of benefiting from the sale of pirated movies and providing business support to two Web sites suspected of offering access to illegal film downloads, according to several people familiar with the matter.
The allegations are an embarrassment for Google, which assured the companies on Friday it would take measures to prevent a recurrence of the episode.
The flare-up comes amid what have been often-tense negotiations between Google and the big film and TV studios over the unauthorized use of copyrighted programming by YouTube, a free video Web site Google bought last year after the site quickly became a cultural phenomenon.
… On Friday, Google responded to the complaints by agreeing to implement a series of measures it believes will help thwart piracy. In an afternoon conference call with studio representatives, lawyers for Google said the company would remove certain ads the companies objected to, create a list of approved advertisers and refrain from selling keywords used by rogue sites to lure users to pirated material. In addition, the Google lawyers said the company would introduce internal guidelines on monitoring keywords and train its ad sales force about how to avoid selling such ads.