Windows 10 - No Windows 9

So, Microsoft is proposing to just skip Windows 9 and is talking about going straight to Windows 10.  Why?  Windows 9 isn't even out yet!  Why not just call the new iteration "Windows 9" anyway?

On the preview page on MSN there is a picture of the "new look" which apparently is a combination of the tiles or "metro" screen along with the familiar start button.

Frankly, Windows 8.1 is not a problem.  The backend is still Windows 7, it is purely a cosmetic change to get the "metro" look.  I'll grant you, a touchscreen makes it much easier to navigate, but 8.1 gave us back the start button (with the right and left clicks reversed...  why?!).

And... do any of you remember?