The next update for Minecraft: Xbox 360 Edition will not include Jungle Biome but 4J Studios hinted at its arrival in a later update.
Having Jungle Biome, one would probably want to reset their world. Any area that are yet to be discovered may have it but areas already discovered wouldn’t.
Since we don’t know what is in Title Update 9 other than the End, which there is high percentage that there is no need to restart to access, nobody knows.
Blacksmith’s chests should be in TU9 since they were added to the PC in 1.1 and that is what TU9 will be.
If they are, there is a need for new world if all villages has been discovered because they’ve already generated.
We won’t know until 4J releases the change log or announces some other features that we know for sure will need a new world in order to use.
As for Jungles in a later update, you will need to start a new world if you’ve already explored your world.
This is the rule to follow. If you’ve already explored your entire world and an update is bringing changes to the terrain, like the jungle biome, you will need a new world.
There is a small, very small, chance that new biomes will appear in unexplored areas of your world.