HIC SUNT DRACONES
Here, "Canon" means comics that are part of the current main timeline of DC / Marvel. Parallel universes such as Ultimate or Elseworlds, imprints like Icon and Vertigo, other companies like Black Horse and Image, and anything else that does not belong to the main timelines belong in Non Canon.
Remember, not everything that is part of the timeline goes here. This is a recommendation list, thus you should include good shit: no Countdown to Infinite Crisis and similar detritus.