I have no experience with this subject, but clicked through in order to think about how I might want to attack such a problem. At a glance, it looks like dzone

I have no experience with this subject, but clicked through in order to think about how I might want to attack such a problem. At a glance, it looks like dzone.com there doesn't even try as the new page is full of accounts which shovel in half a dozen or more links per minute. I'd think that some basic means of rate limiting would be a start, a base cooldown which grows if an account continues to bang into it. From there, further limit and eventually blackhole new links from accounts whose previous submissions fail to gain traction. I'd also think about how to score the trustworthiness and relationships of accounts to qualify submissions. I'd expect that spam accounts wouldn't spend much time promoting stories other than those of their own network. On the other hand, promotion by a trusty account could indicate that a link and the submitting account is less spammy.