The Shark Fin Conjecture
It's a pretty familiar shape, isn't it? I propose we all start to call the temporary large boost in traffic gained from hitting the front page of news sites a shark fin. They are usually created from the massive amount of traffic gained from the first day the article is popular, along with some residual traffic from the article being up part of the second day. If you're lucky and can keep users moving around your website, you should see an overall increase in traffic after the fame is over with (which, as you can see, I had none).