Oh boy. My condolences to anyone who purchased Honour PvP gear last week. My condolences as well to Blizzard, who have accidentally made enemies with pretty much every PvPer recently. I know I sure as hell wouldn't want to be on any WoW PvPers' bad sides. Those people are fucking psychopaths.
6 ilevels might not seem like a lot on paper when most players are running around with at least 350 of them, but the way stats work-- positively affecting each other so overall power increase is more-or-less exponential relative to actual ilevel-- means that this is actually a significant increase to both damage/healing output and survivability, each of those things again positively affecting the other in terms of acheiving success during actual gameplay.
But it's only gear. We all know that. Anyone who actually PvPs regularly will quickly make up the difference. So what's the big deal?
It's because it feels unfair. Gear aquisition is one of WoW's major game systems, and in any game system predictability is essential for the player to feel that they have some control over the outcome [ie, gameplay]. When the outcome changes randomly, the player loses this sense of control and so loses the feeling that they are actually "playing" the game.
Players took the time to gain an understanding of the loot system, determined a strategy to acquire it and executed that strategy, only to have the game change under their feet. And even though they [presumably] enjoyed this gameplay while it was happening, they have now lost faith in the fairness of the system, having learned that their success* or failure will always rely on arbitrary and unanticipated developer decisions ahead of their own gameplay decisions.
Gear is gear is gear, but fucking up a game system like this causes me a loss of respect for the WoW developers. I really would like to see Blizzard "fix" this error by providing the upgraded gear to players who unknowingly purchased outdated gear last week. A social apology is fine for a social situation, but when you are talking about a business relationship with a paying customer, only retards are completely satisfied by nice cheap words. Though I don't have high hopes for this happening, so for some players it may become just another in a long list of dissatisfactions with WoW.
Even so, I'd really like to urge anyone who is upset by this blunder to please remember that it is just a game. While having passion for a game makes it more meaningful and enhances the experience, if it's reached the point where a lack of success in the game causes you emotional distress, you might want to dial it back a bit.
* "success" in this case is acquiring gear which is relatively competitive.