Feature request (and potential pipedream):
It would be helpful to allow the renderer to read worlds created by Minecraft Pocket Edition.
PE worlds contain one RegionFile in little-endian (!) format, and chunks are not Gzipped or wrapped in NBT.
See the code in PocketInvEditor: https://github.com/zhuowei/PocketInvEditor/blob/master/src/net/zhuoweizhang/pocketinveditor/io/region/RegionFile.java for an implementation example. I guess a modification of World and Region should take care of it.
For more info: http://www.minecraftwiki.net/wiki/Pocket_Edition_Level_Format