@Harlequin:Many subtle difference between Win8 and earlier version of Windows means more support calls. With Win8 boots directly into Metro, and they can't find the familiar little icon that kick starts little inhouse application, they'll surely dial the phone.
Service packs don't make users lose icons.
And I'm aware that the "pirate rate" of Win8 for home use is not as high as I had expected, plus lots of customers in computer centre want's sales to help them install Win7 instead of Win8, that means IT supports have to expect most users won't have hands-on experience with the new UI when they rolls out the system.
The support cost would be added is worrisome.