There are two ways to switch between applications win+tab and alt+tab.
Using win+tab all Windows 8 Store apps running are shown individually in the left task switcher. Desktop applications in this scenario are all shown as a single block - "desktop". There is no way to show them individually with win+tab.
Using alt+tab all Windows 8 Store apps running are shown individually in the center task selector. Desktop applications are ALSO shown individually and the user can alt+tab and shift+alt+tab through them as desired.
This is how it works. win+tab simply groups desktop applications like it or not. If you don't like it (and I can understand why not) then use alt+tab (which is the old standby anyway).
Bonus! There is a third way, of course, to switch between applications either swiping from the right with your finger or pointing your mouse to the top-left corner. But I think it was keyboard shortcuts you are really asking about in your question.
Does it work with Win-Tab? – tvStatic – 2012-10-30T22:46:51.470