[piaste]

They fulfill the same desire with less effort.

Most people didn't blog in order to produce great art or advance human knowledge. Those who did, they tend to still blog.

But most regular Joe bloggers just wanted to share ideas or experiences with other people, connect with them, and hear _their_ ideas and experiences. Writing a 500-word blog post was just the means to start a chat in the comments section. For them, Facebook or Twitter do it better.

I remember when Tumblr started (it didn't have a specific culture yet). Some of my blogging friends opened a Tumblr just to share links and pictures, and kept to WordPress for long-form posts. Eventually, they quickly started spending more times in link exchanging and commenting on Tumblr than on WP.