The guys and gals at Blizzard have been extraordinarily busy this year, posting April’s fools left and right.
The first one is a slightly redecorated Armory Profile for each character. I turned into a tusken (see screenshot) and the achievement/activity records have been updated to correctly state “Ninjaed loot” on each item.
Then, there is the Neural Interface for WoW in the Blizzard shop. Not so subtle.
The third one is actually funny, because it has a couple nice details and it is very close to the truth (if you take addons like GearScore into account): WoW Equipment Potency check. Technically, it’s all there – the phasing technology (as used for example in Icecrown for people who haven’t done the Ebon Blade questlines) allows to selectiveley show or hide content (although currently no terrain, I think, but this will change with Cataclysm) according to the player’s status. Item levels determine how “powerful” an item is and can be mapped to a numerical bar. And: check the items that are looted on the screen shots. 