Minecraft wiki entry for Ender_Dragon, associated text: On Reddit, Notch referred to the ender dragon as a she and suggested her name to be "Jean?" in the same manner he called the player "Steve?".[4]
Dinnerbone later stated that he thinks the name is officially "Jean?".[5]
The Xbox avatar item Ender Dragon Pet has the description "A cuter, friendlier version of his bigger, less playful Minecraft sister" - confirming that the ender dragon is female.
Before she was textured, Notch reported that he was afraid to texture the ender dragon as she was a complicated model.[6] In the end, the dragon model was so complex Notch stated that he gave up making the texture manually and wrote a texture packer tool to aid him in adding the texture to the model. Notch also uploaded the code for the tool so others could use the pack. (Link to the texture packer)[7]
Notch joked about how Minecraft was "going next-gen" when deadmau5 mentioned this.[8]
Notch has uploaded a video showing why ender dragons do not spawn in the main world, as they would destroy any block they touch.[9]
On Reddit, Notch explained that ender dragons destroy Overworld matter because "trying to make an AI to properly navigate arbitrary terrain before the code freeze next tuesday [sic] isn't feasible".[10]