Is it the real deal or a mocked-up forge? The WotlK box layout has many exact elements used on The Burning Crusade box. The placement for the Blizzard logo and ESRB rating line up exactly, and the font used to spell 'expansion set' is identical to its cardboard predecessor. In another photo that lends to its authenticity is a printer's mark. The box also notes that you need The Burning Crusade to play Wrath of the Lich King which means no free TBC bundles.
Hopefully, it won't be long until those boxes are stuffed with the goods and shipped to retail where we can pick them up because what comes on the inside of the box is what matters. Unless you're one of those weirdoes that save game boxes and treasures them for eternity. If you are feeling lucky skip the box altogether and try your hand at the WotlK beta-lottery.