Orr will continue in her role as head of consumer media, as well as taking on managing director duties, a spokesman for the firm said.
Bureau has been at CNET for five years, handling the publisher's five-strong portfolio of websites, which includes atlarge.com, CNET.co.uk, GameSpot UK, silicon.com and ZDNet UK. He said he was quitting the media world after 10 years to concentrate on entrepreneurial ventures.
He said: "Digital has been the catalyst for a lot of changes in media in the UK over the past decade and I'm looking to be a part of those changes by getting involved in a project and taking some equity."