Any business running Windows 7 is in a perfect position to upgrade to Windows 8 - the compatibility aspects are so similiar it is a piece of cake to do a phased migration of a few PCs. Organizations in this position would be wise to gradually start upgrading sooner rather than later and get it over and done with.
Not only that I think licensing would be fairly reasonable going from 7 to 8.
Going from XP is a considerable nightmare.
what business care about is first and foremost the business case to upgrade, they dont upgrade because its easy or hard to, they upgrade if there is a business reason to. Also you stating about upgrading from windows 7 when most businesses are not even using windows 7, look at the stats for IE6 and it will give you an idea what OS most are using. Windows 8 I have posted now several posts highlighting problems with it that are things you dont expect in a business OS. None of the posts have receieved any direct reply.
A second thing a business will car about is the impact on its efficiency, any change of UI is going to cause serious doubts.
Yes there may be a few business's using it for the sake of it but it wont be any notable number. Windows 8 is designed to appeal to those who enjoy novelties.
Also you ignored that business's tend to (a) wait for at least a SP1 and (b) their current OS is on its last legs.
So your last line is more relevant given that more business's use XP than windows 7.