I have Windows 8.1 (it's Windows 8 with the 'start' button returned). There are some things I really like and others that I hate. For example If I type in C:\users\louis into the search bar, on older versions of windows it would open up the folder in windows explorer, on Windows 8 it searches for the term "C:\users\louis", other times it'll open the folder as intended. It's frustrating. In fact, I don't really like the "Metro" user interface at all. I very rarely use it.
They skipped Windows 9 because of lazy programmers, back in the 90s there was windows 95 and 98 and programmers would use a wildcard search to find what Windows version a program was using, they'd refer to "Win9*". It's feared that a lot of programmes won't work properly in Windows 9 if they use that code. It seems odd to me too.