Sales of Vista continue to grow at a steady pace after Microsoft said it has now shipped 88 million copies of the operating system.

The sales rise comes despite Vista underwhelming consumers and being snubbed by enterprises. However Microsoft insists that the Vista shipments are now almost double the number of copies of XP shipped in the same amount of time at its launch.

In late July, Microsoft said it had hit the 60 million shipment mark with Vista.

Microsoft launched Vista in January this year and had previously said that it had shipped 20 million copies of Vista in its first month, and 40 million copies of Vista in the first 100 days.

Microsoft credited Vista with helping it beat Wall Street expectations and raise financial projections for the rest of the year. The company reported revenue of $13.76 billion for the first quarter ended 30 September, up 27 percent from the same quarter in 2006.

Three-quarters of the copies sold of Vista were higher-priced ‘premium’ versions, compared to 59 percent of the copies of Windows - primarily XP - available a year ago.

The 88 million figure mostly includes Vista-installed PCs bought by consumers and small businesses, as well as packaged copies of Vista sold in stores or online.

It does exclude the tens of millions of Windows corporate volume licences. There, many enterprises continue to hold off on deploying Vista, acknowledged CFO Chris Liddell, though he expects them to start deploying it when Vista Service Pack 1 arrives in the first quarter of next year.

Based on original reporting by By Eric Lai, Computerworld.