Well, not quite yet. An article in today's New York Times (which does not actually use the phrase "astroturfing") details music conglomerate Warner Bros.' attempt to ingratiate itself with MP3 blogs in order to promote a band called The Secret Machines (who, incidentally, have 2 albums with 8+ ratings on Pitchfork) - with disastrous results:

"I never heard these guys before, but theyre awesome," read a posting last Thursday under the name Ron. "I went to their website and you can listen to a lot of ther other stuff, very cool and very good!" Another post, sprinkled with casual profanity, asserted that big corporations could still release good music, and cited the Beatles as an example.

A check of site records by Mr. Willett revealed that all four of the suspect comments had been posted from the same Internet Protocol address, indicating that they came from the same computer or from a computer within the same company. That address was also the source of two e-mail messages that Ms. Bechtel sent to a reporter, as well as the original messages sent to the bloggers.

When asked for comment, Warner Bros. claimed that "fans of the band who worked at the company" must have posted the messages:
"We're not sitting here typing in message boards that the band is great," she said. "But if somebody in the building loves the band, I can see them doing it. People at record companies are also huge fans."

Possible, but still disingenuous.