See it live at:
What started as a simple WAI-ARIA Landmark Roles Cheatsheet turned out to be a full-blown article about the subject.
Since I had the different elements of the page done, I figured “Why not fill them with content, then?” and that is what I did.
Also, it appears that to date there was no other WAI-ARIA Cheatsheet, so this will prove useful to developers. Hope it does!