Twitter founder steps down as CEO

Twitter co-founder Evan Williams has stepped down as CEO of Twitter, promoting chief operating officer Dick Costolo to take the top seat while WIlliams focuses his attention on “product strategy.” Williams took over the Twitter CEO position from another Twitter founder, Jack Dorsey, in 2007 when Dorsey moved on to become the company’s chairman.

“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,” Williams wrote in the company blog. “”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.’

Some industry watchers are heralding the changeover as an indication that Twitter is serious about converting its operations into a money-making enterprise. To date, Twitter has stepped tepidly into the world of value-added services and charging partners for access to the Twitter “firehose” of real-time tweets. However, converting Twitter into a profitable operation is likely to mean embracing a good deal more advertising and revenue tie-ins. Some long-time Twitter fans fear that could seriously undermine the person-to-person and organic communications experience that Twitter offers.

Williams was a driving force behind the recent changes to Twitter’s Web site, which incorporates spaces for users to view linked photos and videos, as well as potential spaces for advertisements and promotions.

Twitter has experienced massive growth in the last two years, jumping from about three million users in 2008 to more than 160 million today. At the same time, Twitter’s payroll has expanded from a few dozen employees to more than 300.

Williams will continue to work for Twitter; his official title now appears to be “co-founder.” Former CEO Dorsey is still chairman of Twitter’s board. Another Twitter co-founder, Biz Stone, is also still with the company.