North American computer enthusiasts didn't surge to the stores to snap up new versions of Microsoft's Vista, the new operating system and first major upgrade in more than five years.

However, Microsoft said the software is available for the first time by download.

The system, which is the next-generation replacement for Windows XP, has been released in 70 countries. Microsoft also released a new version of Office, its flagship business software and Microsoft Exchange e-mail software.

"Everything's become digital," Microsoft chairman Bill Gates said Tuesday. "The platform allows people to be creative and build new applications, show off new hardware advances."

With five years, $6 billion and 8,000 workers invested, the industry giant is hoping its slogan for Vista -- "The 'Wow' starts now" -- proves true.

The company is hoping the 'wows' will come from users impressed by Vista's 3D graphical user interface, quick search program and security features.

Another highlight of Vista is not having to search for minimized programs as live mini-previews of each window pop open when the cursor is moved along the task bar.

Vista also features small programs known as gadgets which display headlines, weather, microprocessor loads and memory utilization.

However, some critics have charged the "look and feel" have been copied from Apple  Computer's Macintosh OS X operating system.

Hesitant buyers

Despite the buzz, Vista seekers should make sure that they have a robust-enough computer to run the operating system before installing it.

Even then, most security experts advise waiting to buy Vista because hackers will be trying to find holes in the new system.

"Microsoft owns 90 per cent of the operating system market and when you're big, you're a target... just by installing it you are going to be putting yourself in front of the firing squad that's going to be going after Microsoft," Digital Journal Editor-in-Chief Chris Hogg told CTV.ca.

Hogg suggests waiting at least a year until Vista gets the go-ahead from IT professionals and after patches have been released to fix any bugs.

Another reason PC users might not rush out to buy Vista is because they don't know which version they need. With six versions, choosing the right one may prove to be a daunting task.

At $299 retail, 'Vista Home Premium' will likely be the most popular as it features digital media capabilities that allows users to author DVDs and burn in high-definition.

The six versions are:

Windows Vista Starter is designed to allow families and new PC users to learn how to use computers to maximize educational benefits that PCs and the Internet have to offer.

  • Windows Vista Home Basic will cater to users who only browse the web or check email. (Upgrade: $129; Full Retail: $259)
  • Windows Vista Home Premium will add on to Basic by offering a whole bunch of digital media capabilities including DVD authoring software that lets users burn in high definition. (Upgrade: $179; Full Retail: $299)
  • Windows Vista Ultimate will take Home Premium and Business tools so that a user's PC can be geared toward use at work, home or when travelling. (Upgrade: $299; Retail: $499)
  • Windows Vista Business is the new version of XP Pro, but Goffe says the company learned that people didn't like the word "pro" in the title of the previous OS because it made small business think it would be too powerful or complicated. (Windows Vista Business: Upgrade: $249; Full Retail: $379)
  • Windows Vista Enterprise will cater to the more complex business segment that needs an OS that can manage complex IT structures and file management.

With a report from CTV's John Vennavally-Rao and files from the Associated Press