The America-based Russian monkeys behind the animated cutscenes of The Legend Of Zelda CDI Games and I. M. Meen, Animation Magic, were some time later contracted to do the animation for the Warcraft spin-off Warcraft Adventures. Said game was later cancelled due to the popularity decline of adventure gamesat the time but still, they hired the staff responsible for some extremely laughable scenes, even if what few screenshots from the game that have been seen look a lot better than the studio's previous claims to fame.
Development Hell: The upcoming movie. Talk of an adaptation started in 2006, with the current release being a decade later. The plot flip-flopped between being about the First War to being set just prior to World of Warcraft (the reason cited being that the popularity of the franchise was from the MMO, not the RTS'.). Sam Raimi was originally supposed to direct but the project was put off so that Raimi could focus on other films. He eventually left, citing mismanagement on Blizzard's part who had vetoed most of his pre-production work. It was not until 2013 that the movie was finally Saved from Development Hell.
What Could Have Been: The Burning Legion was originally intended in Warcraft 3 to be a playable faction. Remnants of this can be found in the map editor.
The original game was originally intended as a Warhammer Fantasy adaption, but Games Workshops cancelled the contract with Blizzard at a point where the game was far enough in production that Blizzard decided to change the name and release it anyways.
The original version of the Scourge, as envisioned, would use corpses as resources instead of gold. You'd kill creeps instead of mining. This was too hard to balance though.