A good point was made by Ed Bott of ZDNet when he wrote a post that said that businesses were going to use Windows 8 as an excuse to get Windows 7. Sounds like crazy logic, but it makes sense. Businesses are not on the forefront of the technology revolution. They like to play it safe. Right now XP is safe. Windows 7 is not. Next year, presumably in April when Windows 8 is released, it will make Windows 7 safe. Windows 8 will be looked upon as cutting edge technology, but untested.
With the majority of businesses still using XP the growth towards Windows 7 will intensify into acceptance. The result is inevitable. XP and Vista should breathe their last sometime in 2012.
The Economy and The Cloud
That said, the big IF is whether the US economy will improve enough to give businesses sufficient confidence that they can spend money. With the real estate market in the doldrums, jobs moving overseas, inflation, and high debt, businesses are worried that spending too much money may in fact kill their chances of profitability, if not the business itself. So one big issue is whether or not the economy will rebound.
Another issue that is starting to manifest itself, which was not a player when Windows 7 was released, is the Cloud. This allows software and hardware upgrades to be less important, because a company can lease the latest software and hardware from a Microsoft Data Center and make the transition to the most current technology. With Windows 8 coming, it may even supplant the Windows 7 element. All that Microsoft has to do is show that the legacy applications will run on Windows 8.
There is also fact that Windows 8 may have many features currently seen today in tablets and mobile smart phones. So the view that the technology is untested may not applicable, which in turn will allow businesses to make the transition to the most current OS.