Windows 8 was the widest and most deeply tested OS in Microsoft's history according to Steven Sinofsky, which he believes means that the world is ready for Windows 8 and its new workflow. Seeing as Windows 8 was tested so widely when compared to previous iterations of Windows, it should signify that Windows 8 will be another rock solid OS out of Redmond.
Microsoft released three 'previews' over the development cycle (Developers, Consumer and Release) and there were 16 million PCs actively participating in these programs to help iron out bugs and perfect the platform. The Release Preview was downloaded 7 million times that and was launched only ~8 weeks ago.
Windows 8 has been thoroughly tested, to say the least, and it should leave a good impression on consumers from a stability point of view.
You can get Windows 8 starting on October 26th either by upgrading for $39.99 or with the purchase of a new PC. If you buy an eligible Windows 7 PC today, you will be able to purchase an upgrade to Windows 8 Pro for $14.99 (U.S.) through the Windows Upgrade Offer.