EntityID got removed for mob spawners

that is suppose to happen right click a spawner with a mob egg ;]

EntityID got removed. Use Type in SpawnPotentials . See http://minecraft.gamepedia.com/Chunk_format#MobSpawner

SPAWNPOTOTENTIAL ALSO NOT WORKING

See 15w34d - NBT Changes and Additions

It is said that the EntityId is now stored inside the SpawnData tag as id:

Spawner example

/setblock ~ ~ ~ mob_spawner 0 replace {SpawnData:{id:Sheep,Color:1}}

@^Rev, the "SpawnPotentials" tag has been changed quite a bit now. The "Properties" tag was renamed to "Entity". The "Type" tag is no longer used, replaced by an "id" tag inside the "Entity" tag (similar to "SpawnData"). Example:

/setblock ~ ~ ~ mob_spawner 0 replace {SpawnPotentials:[{Weight:1,Entity:{id:Sheep,Color:1}}]}

pre3 using /setblock ~ ~ ~ mob_spawner 0 replace {SpawnPotentials:[{Weight:1,Entity:{id:Sheep,Color:1}}]} - results in a pig spawner

@@unknown It starts as a pig spawner because the SpawnData tag is not populated. Once the pig spawns, it becomes a sheep spawner. If you want it to skip the current entity in SpawnData, you'd set Delay to -1:

/setblock ~ ~ ~ mob_spawner 0 replace {SpawnPotentials:[{Weight:1,Entity:{id:Sheep,Color:1}}],Delay:-1s}