Given that publishers have managed to get Google's ContentID system to misidentify public domain songs, bird songs, and other such things as their exclusive property, bad faith or otherwise negligent copyright claims are a real problem.
Ref: http://www.geekosystem.com/rumblefish-birdsong-takedown/
It's worth mentioning that copyright bots are not even required by law. Google could be complying to dmca requests without automatic take downs. They're going beyond what the law requires because they want to be in Hollywood's good side. So a competitor could still be legal without the bots.
I suppose we might see litigation whenever DMCA notices start getting used for election-related hijinks, though.
See my other comment for a simple scenario that shows why: http://news.ycombinator.com/item?id=4497393
Furthermore, I'm not sure how YC deleting a post and issuing a DMCA takedown request against content on their own site are the same thing. This isn't about deleting content at all. Whether a site deletes content isn't at issue whether it violates copyright or not. The issue is sending bogus takedown requests to others.
I don't think website owners should be prohibited from deleting user content as they see fit. But I do think the takedown bots are different. They are mainly used to avoid lawsuits and to appease the RIAA/MPAA; websites wouldn't choose to use them if left to themselves. I think they cause as many problems as bogus DMCA notices and should be discouraged.
I don't necessarily believe the discouragement should be legal, but maybe. For example, if human oversight was required before the content was removed, that wouldn't necessarily restrict companies' ability to remove content, but it would minimize bogus takedowns by bots.
Again, I'm not really staking a position here, I'm just trying to start the conversation while I figure out my own views on the subject.
Sure it would; it'd make spam removal impossible, for example.