1.7.10/Vanilla
On occasion I will encounter a Massive Taiga, Desert, or Jungle biome (thus far) that will extend near indefinitely and with the girth of at least 8 normal sized biomes.
An example of this is:
Seed: 1069692326179493227
Coords: X: 1300 Y: 60 Z: 5000
Note: This is a massive Jungle Biome
Does anyone know if this was an intended feature or just the result of bad generation?