Twitter, Skype appoint new chiefs

Twitter has promoted its COO to the CEO post in place of co-founder Evan Williams, while Skype has tapped a Cisco exec as its new chief.
Williams has handed the reins to Dick Costolo, who joined the startup as COO a year ago, to allow the outgoing boss to focus exclusively on product strategy.
“I am most satisfied while pushing product direction,” Williams said. “Building things is my passion, and I’ve never been more excited or optimistic about what we have to build.”
Costolo has been a CEO three times in his career, Williams pointed out. “When I insisted on bringing Dick into the COO role a year ago, I got a lot of questions from my board. But I knew Dick would be a strong complement to me, and this has proven to be the case.”
Costolo is also a former product manager at Google, and was one of Twitter's early investors.
Williams is Twitter's second CEO – after fellow co-founder Jack Dorsey – to resign from the job after a two-year term.
Twitter's executives have yet to find a way of making money from the phenomenally popular microblogging service, but have recently started experimenting with methods including advertising via the Promoted Tweets service.
Meanwhile, Josh Silverman has quit VoIP market leader Skype after a little over two years in the job, and will be replaced by Tony Bates, head of Cisco’s enterprise division, at the end of the month.
CFO Adrian Dillon will serve as interim chief until Bates joins the company.
The shake-up comes at a crucial time for Skype, as owner eBay plans to float its subsidiary on the Nasdaq this year via an IPO that could be worth up to $100 million (€72.6 million).