It looks like Kim Dotcom's arguments might not have been as watertight as he insisted: Universal Music Group has released a statement saying that some of the artists featured in the I Use Megaupload video didn't consent to their image being used. The Megaupload founder succeeded in his original plea to YouTube to have the video reinstated, only for UMG to issue another DMCA takedown notice leading to the video vanishing again. Megaupload has since filed a lawsuit against UMG for misrepresentation of copyright, requesting an injunction that would prevent the music giant from censoring the video, along with damages. The lawsuit also seems to accuse UMG of censoring its artists, stating that "it appears as though UMG and Defendants are abusing the DMCA takedown mechanism to chill free speech they do not like."
For its part, Universal Music told GigaOm that some of the requests have been filed on behalf of the artists or their representatives, and that "at least one of them has already sent a takedown notice for this unauthorized use." This does make you question why an artist would say something to camera and not expect it to be used, though.