Microsoft proud of its first 'post-Gates' OS, Ballmer says.

Windows 7 is the first Microsoft OS developed away from the watchful eye of Bill Gates, and the technical leaders who built it had to adjust to life at the company without its cofounder and former chief software architect, CEO Steve Ballmer said Thursday.

"We have a lot of people who are stepping up and growing in new ways," Ballmer said, speaking at the McGraw-Hill 2009 Media Summit in New York. "There's no question about that. I'm growing in some new ways. Some of the senior technical guys are growing in new ways."

Windows 7, which is expected to be out later this year, is a product of some of the changes that have taken place since Gates left, and Microsoft is proud of the result, he said in an on-stage interview conducted by BusinessWeek Editor-in-Chief Steve Adler.

"It's a great piece of work," Ballmer said. "And it's a piece of work that was driven by a team ... independent of Bill and his leadership. And I think we're all, you know, feeling pretty good about it. We've got to finish it. But I think it'll be a big, big deal."

Indeed, Windows 7, a beta release of which is available, has already received positive reviews from early users. Its predecessor, Windows Vista, took more than five years for Microsoft to develop and was received poorly by many businesses and consumers.

Without saying so explicitly, Ballmer hinted that he and colleagues were limited in their ability to make certain technical decisions at Microsoft while Gates was there. Gates left his day-to-day duties at Microsoft last July to work full time with the philanthropic organization he formed with his wife,The Bill and Melinda Gates Foundation. Microsoft Chief Software Architect Ray Ozzie and Chief Research and Strategy Officer Craig Mundie share Gates' former responsibilities.

Ballmer said the "number-one thing" that's changed at the company is the way he, Ozzie and Mundie interact as a team to make technology decisions. "The way the three of us accomplish, let me call it the job at the center of technology leadership, is certainly different than the way Bill did," he said.

Gates, on the other hand, had more of the final say himself in technical decisions, Ballmer said.

"He was the founder. I might have been the CEO, but he was 'the Bill,'" he said. "There was no question that if Bill thought something should be done ... he actually didn't give orders much, but if he thought something should be done, you knew life would be intense if you didn't agree. Let me say it that way."

Still, he said, given the choice, Ballmer and his colleagues would be happy to have Gates back.

"We miss Bill," he said. "I mean, if you gave sort of the average senior technical person at Microsoft a vote, 'Bill back, Bill not back,' they'd probably say, 'Yeah, it'd be great to have Bill back.' On the other hand, Bill's doing something important that everybody values, and I think everybody relishes the opportunity to grow and take more responsibility."

Ballmer declined to say when Windows 7 would be available, saying only that the company would release it "when it's ready." The official word from Microsoft is that Windows 7 will ship three years after Windows Vista, which was released to business customers in November 2006 and to the general public in January 2007.