Breaking: Twitter's Evan Williams is stepping down

Evan Williams, who helped popularize communicating in 140 characters at a time, is stepping down as CEO of Twitter.  In a Twitter blog post entitled, #newtwitterceo, Evan said:

The challenges of growing an organization so quickly are numerous. Growing big is not success, in itself. Success to us means meeting our potential as a profitable company that can retain its culture and user focus while having a positive impact on the world. This is no small task. I frequently reflect on the type of focus that is required from everyone at Twitter to get us there.

This led to a realization as we launched the new Twitter. I am most satisfied while pushing product direction. Building things is my passion, and I’ve never been more excited or optimistic about what we have to build.

This is why I have decided to ask our COO, Dick Costolo, to become Twitter’s CEO. Starting today, I’ll be completely focused on product strategy.

This leaves Evan to focus on, among other things, building a better user experience at Twitter.