The reason for skipping 9 is because they think it will cause confusion with Win 98.
I don't see it, but we are talking Microbloat.
It had to do with some older software that would check for Windows version Win 9x and didn't care what came after the 9. Apparently it was a big enough issue they decide to skip 9 and go directly to 10.
I can't wait, but I'm a die-hard like that.