Microsoft officially launched Windows 8 and Windows RT at a massive event New York City, complete with takeover of more than 39 digital boards in Times Square. The operating system will be available in stores tomorrow, but you’ll be able to get a head start at 12:01 a.m. by visiting the Microsoft Store’s pop-up location in Time Square or Microsoft’s website, where you’ll be able to download the OS for just $40.

During the Windows 8 launch webcast, Microsoft Windows and Windows Live President Steven Sinofsky noted that Windows 8 has undergone more than 1.24 billion hours of testing, and pre-release versions of the OS have been downloaded more than 16 million times. While there are more than 1,000 new PCs which have been certified for Windows 8, the OS will run extremely well on the devices you already have at home, improving performance by 13-50%, depending on the hardware. Wi-Fi, for example, can now reconnect in just a second, rather than the 15 seconds that Windows 7 required.

The Redmond-based devices and services company promises that Windows RT, the version of Windows 8 designed for thin-and-light ARM-based devices, will be just as reliable and secure one year from now as it is today. Better still, all Windows RT devices are compatible with more than 420 million devices and peripherals out of the box. 50 of the top 53 printers, for example, will instantly begin working with your new Windows RT (or Windows 8) PC.

Windows RT is not compatible with Windows 7 applications, but it supports nearly all of the apps in the Windows Store. “We see today as a Grand Opening,” said Sinofsky, “and a solid one.” Thousands of new apps are arriving every week, and the Windows Store already has more apps than any competing app store had at its launch.

Windows 8/RT will be available on millions of PCs in a few hours, from great low-end devices to spectacular high-end devices. Microsoft claims that everyone will be able to find the perfect device for their needs, be it for personal use or in an enterprise. As Microsoft CEO Steve Ballmer happily stated, “Windows 8 PCs are the best PCs ever.” Don’t believe him? Check out our review.

Update: Microsoft also launched the Surface at an event a few hours later. For the full recap, check out our sister site Anythingbutipad.

[Microsoft News Center | The Windows Blog]