NEW YORK -- For a company that has launched products with Ringo Starr, Paul McCartney and Jay Leno -- and has even paid to light up the Empire State Building in its signature colours -- Microsoft's unveiling of Windows 8 on Thursday was a subdued affair.

Windows 8 is Microsoft's radical reimagining of its ubiquitous operating system. What makes it vastly different from past Windows releases is that it's designed from the ground up to work on touch-enabled PCs and tablet computers. Microsoft is also making its own tablet computer, the Surface, marking the first time that it will manufacture a general-purpose computer. Both the Surface and Windows 8 will go on sale Friday.

For the event, Microsoft dressed up a cavernous former bus depot on a floating pier jutting from Manhattan into the Hudson River. Improvised siding shielded the roughly 500 reporters and other guests from the sight of a ruined pier to the south.

This time, with no rock stars in attendance, Microsoft executives took the stage to introduce an array of Windows 8 desktops, laptops and tablet computers made by AsusTek Computer Inc., Dell Inc., Samsung Electronics Co. and others.

Instead of raising expectations, Microsoft Corp. did what it could to reset them.

In recent days, some reviewers have panned Microsoft's Surface tablet. Others have criticized the dearth of apps in the Windows Store, the new online store where customers can buy apps that will work on the current model of the Surface and other devices that use the streamlined version of the new operating system, called Windows RT.

"The Windows Store has more apps than any competing app store had at its opening," said Steven Sinofsky, president of Windows and Windows Live, in a thinly veiled reference to Apple Inc.'s iPad, which launched in April 2010 relying on apps that had been developed for the much smaller iPhone.

"Thousands of new developers are joining the Windows Store ecosystem," Sinofsky added. "Your PC experience only improves over time."

Microsoft's U.S. launch event followed a pre-launch event in Shanghai on Tuesday.

Launches such as Microsoft's inevitably draw comparisons with Apple's events. Microsoft's event in New York took on the look and feel of Apple's famous unveilings but lacked the element of surprise. Apple's late founder and CEO Steve Jobs used to tease audiences with "one more thing" at the end of Apple presentations. Most of what came out Thursday had already been known long ago -- a consequence of Microsoft's need to work with a wide array of partners, particularly PC makers.

Microsoft's event was tame even by Microsoft standards. For the Windows 95 launch, founder Bill Gates brought Leno to the stage to show how easy the software was to use. In 2009, McCartney and Starr helped promote the "Beatles: Rock Band" video game during Microsoft's presentation at a game conference in Los Angeles.

In the one extravagant touch of the Windows 8 event, Microsoft built a miniature model of Manhattan out of wooden boxes. It was painted white and covered an area the size of a basketball court. Reporters could walk among the buildings to peruse Windows 8 devices --desktop PCs, notebook computers and tablets-- perched on their "roofs."

Sinofsky was the first to appear on the stage Thursday, standing before a light blue background amid a row of devices from various manufacturers. He wore a blue V-neck sweater over a white T-shirt. CEO Steve Ballmer later appeared in a suit and unbuttoned collar with no tie.

Microsoft executives said 1 billion people are using Windows and 11 billion photos are stored on its cloud storage service, SkyDrive.

They borrowed from Apple's phrase book, frequently relying on superlatives to describe Windows and the machines and gadgets that run it. Sinofsky said the release was "the best release of Windows ever" and the array of PCs, tablets and "convertible" tablet-PCs were "the best PCs ever made."

Perhaps in a nod to its many manufacturing partners such as Dell and others, Microsoft didn't talk about its own device, the Surface tablet, until the end of its morning presentation.

It followed that with a separate presentation in which Surface general manager Panos Panay dropped the tablet from shoulder height to the stage without breaking it to demonstrate the toughness of its glass and magnesium case. Sinofsky also showed off a couple of Surface devices the team had turned into skateboards by screwing on rails and wheels.

Ballmer, wrapping up an initial presentation, appeared to address concerns that the new Windows 8 interface, which emphasizes touch, has annoyed some early PC reviewers.

"Windows 8 shatters perceptions of what a PC now really is."

Later, he addressed a concern that some PC users have had with pre-release versions of the software -- that it lacks a familiar "Start" button containing programs, settings and other controls. Microsoft has said its new interface, with its automatically updating tiles on the opening screen, replaces that button.

Asked by an Associated Press reporter if he might bring the "Start" button back, Ballmer replied, "You've got a whole screen as a 'Start' button," while hurrying off.