Microsoft 8 is in its "final phase" of development following the Release Preview launch of the new operating system.

This new preliminary version can be downloaded at http://preview.windows.com and its interface is available in 14 languages, Microsoft said yesterday.

Microsoft also announced that starting on June 2, it will offer a Windows Upgrade programme in 131 markets so that consumers who buy participating Windows 7 PCs through January 13 of next year will be able to purchase an upgrade to Windows 8 Pro for an estimated retail price of $14.99 during the promotion period. Microsoft will later announce details of a similar programme aimed at consumers who have already bought Windows 7 PCs.

The previous Windows 8 test version, called Consumer Preview, was released in February and downloaded more than one million times within its first 24 hours of availability. At this point, Windows 8 is the most tested Microsoft operating system ever, according to the company.

Windows 8 tablets

As with any other major Windows revamp, much is riding on Windows 8, which has been designed with tablet devices in mind. As iPad and Android tablets sell by the millions, Windows is a minor player in this market, putting Microsoft at a disadvantage not only among consumers but also among corporate buyers.

There is much expectation among industry analysts and market observers related to how well Windows 8 will do once it's released in general availability. Microsoft hasn't given a date for its shipment, but the consensus is that it will probably be available before the end of this year.

Steven Sinofsky, president of Microsoft's Windows and Windows Live Division, said that, if the Windows 8 development continues at its current pace, it's likely that the OS will be available "for the holidays." That would apply both to Windows 8 for devices based on x86 chips from Intel and AMD, and to the Windows 8 version for devices based on ARM chips, called Windows RT.

Some have speculated that most enterprises may bypass Windows 8 altogether, because many companies are just now upgrading from Windows XP to Windows 7. Enterprises typically do desktop OS refreshes every three to five years, and sometimes wait even longer to embark on what is a very complex and costly upgrade process.

Metro UI

That's what recent research from Forrester Research indicates, according to Forrester analyst David Johnson. "It'll be a slow uptake in the enterprise for Windows 8," he said.

More likely drivers of Windows 8 adoption will be consumers buying new Windows 8 PCs for personal use, and buying tablets to take advantage of the "bring your own device" trend, where consumers would use Windows 8 tablets both at home and at work, he said.

"IT organisations won't willingly adopt Windows 8. They'll have to be pulled into it," Johnson said.

It also remains to be seen how enthusiastic tablet makers will be about making Windows 8 tablets, and ultimately how successful those devices will be in the market.

Some critics have questioned Microsoft's decision to include two user interfaces with Windows 8 - the traditional Windows desktop and the new Metro interface, designed for touch-based screens - because they feel the user experience could be clunky and problematic.

Do Not Track default

Another open question is how much support Microsoft will be able to muster among ISVs (independent software vendors) for creating and porting existing applications for Windows 8 and the Metro interface, according to Forrester's Johnson.

Microsoft, naturally, is doing its best to create excitement about Windows 8, and touted improvements and additions in the Release Candidate, including new applications built by the company and some of its partners. Specifically, the Mail, Photos and People applications that debuted in Consumer Preview have been enhanced, the company said.

Among the "tens of thousands" of tweaks made since the Consumer Preview are more personalisation options for the Start screen, better multimonitor support and new security features for parents to monitor and control their children's online and PC activities.

Release Preview also features improvements to Internet Explorer 10, the upcoming upgrade of Microsoft's browser, including the ability to "flip ahead" on touchscreen devices and an integrated "touch-friendly" Adobe Flash Player. IE 10 also comes with the "do not track" setting turned on by default.