There's lots of questions going around on the changes in the Honor system coming up in patch 1.12, but not a lot of clear answers, so let's pull out the old nerdulator and crunch some numbers.
First, if you're just wondering what the story is and don't care much about the numbers, the news is good for most of you. Basically, you'll be able to get more kills on the same person before they're worth no honor at all. Additionally, Blizz is changing the honor curve a bit-- even though there's no numbers on that yet, they say it's "to allow more people into the ranks." So we assume that's good news for most of us-- if you're one of those players who farms honor in the battleground for forty hours a week, you're probably not real happy about that, because there will be more higher ranks walking around. But then again, you were probably one of the kids who messed up the grading curve for the rest of us in math class.
But speaking of math class, let's see what they're actually doing with the "diminishing returns" on honor kills. Currently (before 1.12), there is a diminishing return of 25% every time a PVP player gets killed. That is, the first time they're killed, 100% honor is given (the actual number of honor is based on all kinds of other factors-- the ranks and levels of the players involved, whether you're in a group or raid, and a few other things). Then, the second time they're killed, 75% honor is given, then 50%, 25%, and on the fifth time they're killed, no honor is given. But in 1.12, we're told that the diminishing return will fall back to 10% per kill. The first kill, then, will grant 100%, but the second will grant 90%, then 80%, and so on and so forth. Which means you'll be able to kill the same player more times, while still gaining honor.
So the big question is, how much more honor will we get? (We told you we were pulling out the nerdulator for a reason.) Just for calculation, let's use an honor score of 100. Under the system before 1.12 (the formula is 2.5x, if you want to get really nerdy about it), you'll get 100 + 75 + 50 + 25 + 0 = 250 honor before your target is honorless. Under 1.12 (formula: 5.5x), you'll get 100 + 90 + 80 + 70 + 60 + 50 + 40 + 30 + 20 + 10 + 0 = 550. That's a whopping 220% more honor before every kill goes honorless. Sounds nice! Except that everybody else is getting honor at the same accelerated rate, too. So not so fast on shopping for that new High Warlord gear. Blizzard's updating of the ranks curve will help get you the rank you want, but the new honor kill decay rate just means there's lots more points for everybody to fight over.