Vista has been throughly rejected by enterprises with just about one in 11 organisations running the operating system. That's according to a report from Forrester Research which found that just 8.8 percent of large enterprises were running Vista, compared to the 87.1 percent running Windows XP.

Thomas Mendel, who wrote the report said that this implies that most of the PCs upgraded to Vista were those running older versions of Windows, such as Windows 2000 or 98.

"Vista is 'new Coke'," Mendel wrote, comparing Microsoft's flagship operating system to the ill-fated soft drink. Enterprises still on the fence about Vista would be wise, he said, to "consider following the lead of Microsoft's important partner Intel and re-evaluating the case for Vista."

Mendel's comments undercut the momentum for Vista claimed by Microsoft, which says it has sold 180 million licences for its 18-month-old operating system to PC makers and end users.

Vista still has double the share of Macs among big businesses, however. The share of Macs grew to 4.5 percent in June from 3.7 percent in January 2008.

Linux's share of desktops, meanwhile, fell significantly, according to Forrester, to 0.5 percent in June from 1.8% in January.

As a result, enterprise application developers only need to "develop exclusively for Windows XP and Vista. Forget about Macs unless you're aiming at a specific business vertical where Mac use is prevalent."

Forrester's study examined the browser as well as the desktop operating systems of the 50,000 users surveyed. It found that 19.4 percent of enterprise users are using Firefox, up from 16.8 percent at the beginning of the year. Meanwhile, Microsoft Internet Explorer's share only slipped slightly, from 79.1 percent in January to 77.6 percent at the end of June.

"At least make sure that applications work on Firefox as well as IE - this is a must," Mendel wrote.

Both Flash and Java were nearly ubiquitous. Flash Player Version 9 was on 97 percent of desktops, while Java was on 99.9 percent of them. But application developers shouldn't try too hard to jazz up their apps with Flash elements - "business users don't want to hunt for navigation nor do they crave excitement," Mendel wrote.