[gtirloni]

In a recent book (Visual C# Step-by-Step) the author keeps making a distinction about Windows 7/8 and Windows 8.1. I suppose it's because it's relevant but I have not really researched what the differences are from 8 to 8.1.

MS probably feels they are significant enough to keep calling it "Windows 8.1" as the product name. At the same time, Update 1 might be insignificant enough that it's not worth calling it "Windows 8.2".

[rbanffy]

After all, we must conserve resources as limited as release numbers...

[gtirloni]

While I appreciate the joke, you miss the point. This has more to do with marketing strategy than with release numbers used by developers. But I don't feel like discussing such small matter.