Relmstein's latest post asks an interesting question: will the removal of diminishing honor returns in patch 2.4 help Blizzard combat the ongoing AFK problem? His suggestion is that removing the diminishing honor will mean that there is more honor available in the BGs, and that that will drive players back from the "peace cave" out into the battlefield (since they were only AFK-ing because they didn't think they could earn honor fast enough.
But I've got to disagree-- people were (and are) going AFK not because they couldn't pick up enough honor, but because they didn't want to play at all. Going AFK is free honor, and it will keep being so until Blizzard just plain cracks down and starts kicking AFKers. Diminishing honor returns means nothing to serious AFKers-- all they care is that they're earning honor for free. When (or maybe if) Blizzard stops that from happening, then they'll be able to stop AFKers.
As for the removal of returns, I can only think that it'll mean, if anything, more honor farming and turtling. Blizzard says they've crunched the numbers and determined that it's the right thing to do, but I don't see how supplying those Iceblood turtlers will constant honor is going to help things. We'll have to see what effects arise when the new patch drops on the PTR.