> Expect that to change rapidly, given that Microsoft has just
> officially announced the end of life for Windows XP.
They announced that long ago. The stabilization level of XP is around a third with the benefit going to Windows 7. Even Microsoft has tossed a bone to those that won't be upgrading from Windows XP. They are going to keep supporting Microsoft Security Essentials and their malicious software scanning tool into Spring 2015.
> There is now an enterprise benefit to moving directly to
> Windows 8.1, since Microsoft will support it for longer than
> Windows 7.
This has been known for a long time too. There was tons of work in the Boston area doing corporate migrations last summer and fall. I think that a lot of that business is done and it was to 7; not 8 or 8.1. Who knows how long Microsoft will provide support for Windows 7 - I suspect that they will have the same difficult EOLing it as they did with Windows XP.
BTW, 95% of the worlds ATM use a Windows XP variant - Microsoft will have to support those terminals. I'm sure that they will charge a pretty penny for supporting them.