Dear smartypantsweb

What's the purpose of having jumps ("Click for more...") on long blog articles?

I'm not talking about sites that break stories across 10 short pages so that they can expose you to 10 times as many ads. I mean the click-once-to-read-the-entire-post style that I very often see on popular blogs. Random example: Andrew Sullivan puts a "Continue Reading [topic]..." link at the bottom of posts which reach past a certain vertical length, maybe one out of every four of the posts on the front page.

I can guess some reasons, but what reasons does the conventional wisdom hold? (Yes, I'm wondering if we should institute something like this for the Gameshelf.)