Am I the only one to think that "social news" websites, from the perspective of the content publisher only work when the site is small enough?

I mean, the quantity of information being submitted to Digg, and maybe Reddit, is so huge it roughly gives a new story about 5 minutes of exposure in the first page of the New Stories section, and only in the specific feed, not the global one...

It makes me think that somehow, spreading something over Twitter, using our friends to do it, might achieve a better result...