On the plus side, my employer licenses its software by the product type and not the version, so there's no charge to upgrade to a new version when a new version of the OS comes out. That's not unique; a few of our competitors do the same thing as well, but others like to license by the version, so that when a new OS comes out, a new version has to be bought to support it (or an additional software maintenance agreement has to be purchased).
I wish it were solely my opinion. However, it is a fact. I should probably point out that my employer develops kernel mode drivers, some of which make use of protected APIs. It suspect it is quite different if you are developing user mode applications, though.