NEW YORK (AP) - "Wow" hasn't tended to be a big part of Bill Gates' vocabulary, but to hear him speak in the hours before Microsoft Corp.'s planned launch of the long-awaited Vista operating system, you'd never know it.

"This 'Wow' thing is a great way of describing what we've got here," Microsoft's chairman said in an interview Monday as the software maker began a slate of splashy events in New York. "There are chances for wows all over the product."

More than five years in the making, Vista was released for businesses Nov. 30, but the unveiling for consumers of the latest edition of Windows - which runs more than 90 per cent of the world's PCs - was scheduled for Tuesday around the globe. Vista retails for US$100 to $400, depending on the version and whether the user is upgrading from Windows XP.

Over the weekend, Dell Inc. started taking orders for PCs with Vista for delivery Tuesday and beyond. Kevin Rollins, Dell's chief executive, said at a launch event Monday that the company's website saw a 20 per cent jump in traffic and that "tens of thousands of copies" of Vista were sold.