That's pretty much the premise that sites like reddit and HN operate on at the link level, too - most people only read the first page or two, but some people ar

That's pretty much the premise that sites like reddit and HN operate on at the link level, too - most people only read the first page or two, but some people are interested/obsessed enough to go through the dreck and flag up what's interesting. It seems to scale reasonably well so far.