How do Heroic Instances work?
Heroic Instances are supposed to be the equivalent of 5 Man Raids so people should not expect them to be level 70 versions of a lower level instance, they are actually harder. ALL current 5 Man Instances in Outlands can be done in Heroic mode and you must be of Exhaulted Status in the corresponding Reputation Faction to be able to do an instance in Heroic Mode.
The last “wing” for most Instances also required a Key to enter and all the keys are updated for Heroic Mode, requiring you to get new keys.
Lastly, killing Bosses in Heroic Mode drop tokens that can be redeemed in Shattrath for the following items off of G’eras, the Token Vendor. I don’t know if the Heroic Mode bosses drop other forms of loot or if basic green/blue loot off the trash mobs is upgraded for Heroic Mode, though it stands to reason they would be…