This is a good diagram that explains some of the online activity that happens when blog content is generated.
This via Wired.
You compose a new post. You click Publish and lean back to admire your work. Imperceptibly and all but instantaneously, your post slips into a vast and recursive network of software agents, where it is crawled, indexed, mined, scraped, republished, and propagated throughout the Web. Within minutes, if you've written about a timely and noteworthy topic, a small army of bots will get the word out to anyone remotely interested, from fellow bloggers to corporate marketers.
The Life Cycle of a Blog Post, From Servers to Spiders to Suits -- to You
