One thing missing from Thursday's launch event: partners, such as PC makers, on stage.
With the launch of Surface, Microsoft is competing with some of its partners. One analyst suggested that PC makers didn't want to come because of that, as going alone in a presentation was unusual.
"Maybe it's a freeze-out because of the Surface," said Richard Doherty, CEO of technology assessment and market research company Envisioneering.
Larson-Green said there was no such tension. She said PC makers gave Microsoft devices to show on stage, and representatives from each of them were in the audience.
"We made it a Microsoft event to keep it short," Larson-Green said.
The event clocked in at less than an hour. By contrast, Apple's event Tuesday went about 75 minutes — and that was short for the company. That event didn't have any partners either, though past events from Apple have had them.
Included with Windows 8 is a new version of Microsoft's browser, Internet Explorer 10. Microsoft says it's "perfect for touch" and will be designed to work seamlessly with its Internet-based storage service, SkyDrive. It's similar to how the latest version of Apple's Safari browser on Mac computers works with its iCloud storage service. In the case of Apple, Web pages open on other machines logged in with the same account can be easily accessed.
One of the biggest changes with Windows 8 is the disappearance of the familiar start button at the lower left corner of the screen. It has been used to pull up a menu of applications and settings, and to shut down or restart the computer. Instead, people will have to swipe the edges of the screen.
There will be a new screen filled with a colorful array of tiles, each leading to a different application, task or collection of files.
Reached off stage, Ballmer was asked by The Associated Press whether there was any chance of bringing back the start button.
"You've got a whole screen as a start button," he said, referring to the screen of tiles.
At least one PC maker is restoring the start button in an effort to minimize the potential frustration caused by Windows 8's new look. Samsung Electronics Co. has announced models in which it built its own, optional start button that could be used to pull up a menu of applications.
During the presentation, a Microsoft executive had noted that the start button was something people had to get used to when it was first introduced, suggesting that people will get used to the new tile format, too.