http://www.mojang.com/2012/10/minecraft-pretty-scary-update/
Latest patch notes bring the Withering to Minecraft...
EFU isn't the first story telling group to use the suffix or prefix the word wither to a monster. Wither skeletons live in the nether, you kill them, take their heads and combine them to summon a wither boss. Which is a floating thing that shoots fireballs all over and cause damage and your hp bar to become invisible/difficult to read.
I wouldn't be so quick to jump to a conclusion. While it's certainly possible (we had a developer of nwn 2 iirc at one point) I wouldn't base the assumption on this particular update.