Instead, Viacom apparently did keyword searches on YouTube for any terms that were potentially connected to Viacom content, and then asked YouTube to remove any and all clips connected to those terms. One result: YouTube this weekend purged some completely legitimate user-generated video that had the misfortune of sharing keywords with Viacom content.

For instance, blogger Jim Moore, a senior fellow at Harvard's Berkman Center for Internet and Society, complained this weekend that Viacom removed a video of him having dinner with friends at Redbones in Somerville, Mass. Then, to add insult to injury, YouTube warned him: "Repeat incidents of copyright infringement will result in the deletion of your account and all videos uploaded to that account."

It's unclear at this point how many non-infringing videos were caught in Viacom's dragnet, but some other examples have already surfaced on the site Toptensources.com, which this weekend put out a call for clips wrongly removed from YouTube.

On one hand, YouTube's initial reaction -- take down first and ask questions later -- is understandable. The Digital Millennium Copyright Act generally absolves Internet companies of liability for content uploaded by users, provided the companies comply with demands to remove pirated material. That law gives companies like YouTube a good reason to acquiesce to cease-and-desist requests -- even the bogus ones. But companies like Viacom should remember that they, too, risk being hauled into court if they misuse the DMCA.

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