Updated

The world's most famous corporate blogger, Robert Scoble, credited with helping to break down a siege mentality at his employer, Microsoft Corp. (MSFT), confirmed on Sunday he is leaving to join a recently formed Silicon Valley Internet media start-up.

Scoble, 41, said in a phone interview that he will join PodTech.net, a Menlo Park, California, start-up that earlier this year began "podcasting," or broadcasting over the Web, video interviews recorded with technology industry luminaries.

Starting in July, Microsoft's best known non-executive employee will become PodTech vice president of content, in charge of creating shows for the new medium in which computer users watch television-like interviews over the Web.

In a posting late Saturday on his widely read blog site Scobilizer (http://scobleizer.wordpress.com/), the Microsoft technology evangelist said he was parting with the Redmond, Washington-based company on cordial terms.

"I love Microsoft and Microsoft did not lose me — at least as a supporter and friend," Scoble wrote on his blog Saturday. "It is the best big company in the world."

While earning Microsoft a newfound reputation for openness that counteracted its reputation as arrogant business partner, Scoble also came to define the paradox of the corporate blogger as both personal commentator and informal corporate spokesman.

Scoble played multiple roles in and outside Microsoft.

Inside, he was a kind of roving reporter, exposing the thinking of more than 700 employees through video interviews available to the public on a Microsoft corporate blog called Channel 9.

Outside, he became known for his commentary on Internet industry trends through his blog and via a book he co-wrote with Shel Israel titled: "Naked Conversations: How Blogs are Changing the Way Businesses Talk With Customers."

Using his blog as a soapbox, Scoble came to personify a new style of corporate honesty in which he publicly spoke his mind on controversial topics. He was often willing to judiciously criticize Microsoft or praise its most fierce competitors.

By resisting the role of corporate propagandist, he has won a following among millions of blog watchers as an insightful commentator on blogging, the software industry and the insular world of high-tech culture.

News of his departure broke in classic blog fashion when Andy Plesser, a New York technology publicist, posted a note on his video blog at http://www.beet.tv that said Scoble had let slip he was joining PodTech.

"It got out before I was completely ready to talk about it," Scoble acknowledged.

Like many bloggers, Scoble mixed in frequent musing about his personal life with his observations about developments within Microsoft and around the Internet.

Frequent readers knew he earned a salary of "less than $100,000" and that, last month, his mother had suffered a sudden stroke, which resulted in her death, according to other bloggers, on May 25.

In his new job, Scoble said his salary was over $100,000 and accompanied by "a quite aggressive stock option" offer that could make him wealthy if his new company succeeds.

"If we make this thing fly, I make more money than I would at Microsoft. If it fails, I don't," he told Reuters.

Scoble, a software marketer who picked up on the emerging blogging trend in 2000, said he had told Microsoft Chief Executive Steve Ballmer that he wanted to "put a human face on Microsoft and he took me up on that."

Microsoft's willingness to give Scoble freedom to publish his often outspoken views in turn fostered an appreciation of the changes going on inside Microsoft that softened up its reputation for being a monopolistic destroyer of start-ups.

"We are sorry to see Robert leave Microsoft," a spokesman said via e-mail. "Robert made a strong contribution through Channel 9 and his blog during an important time for the company."

On his blog, Scoble said he was confident Channel 9 would endure without him at Microsoft. He recalled how Chairman Bill Gates had advised executives attending a CEO Summit last month to start their own corporate blogs in the spirit of Channel 9.

Scoble's offers succinct advice to other corporate bloggers who wish to keep their day jobs: "Understand your company's culture before you start mouthing off. When you start breaking the rules, you better know you are breaking the rules."