With the introduction of Warbands, the Human Racial Diplomacy will be reworked, no longer providing bonus reputation.
Blizzard stated in their War Within Warbands Preview post that the beloved Human racial, long used by players to gain an edge on Reputation grinding, will be reworked due to Warbands affecting alt and account progression:
The human racial Diplomacy is currently designed to grant a bonus 10% to reputation for players who choose that race. Unfortunately, with Warband reputations, this racial causes problems due its character-specific nature.
We don’t want players to feel compelled to play a specific character or race to earn Warband-level rewards more efficiently, so we will convert this race-specific bonus into something new.
Read more on wowhead.com