It looks like Blizzard is finally starting to take this issue of AFKing in Alterac Valley seriously, and not just with the AFK-reporting feature that you've likely already heard about.
In response to one poster who begged Blizzard not to implement this reporting feature because he says the map is imbalanced and the Horde always loses anyways, Drysc gave us a relatively long list of changes that Blizzard is making in order to help solve the problem -- not just reporting AFKers, but also finding other ways to encourage them to get in the game as well, such as fixing exploits, changing or removing NPCs, and yes even modifying the map a little bit.
Here's what he said:
There are quite a few changes coming, all of which we hope will culminate into making players want to participate, and ultimately win the battleground.
Obviously as most people know we have the anti-afk reporting measure, by which you can right click on someone in the battleground and mark them as AFK. With enough reports they receive a debuff that keeps them from earning honor in that battleground, and only by entering combat can they remove that debuff. It's going to help, but it's certainly not enough on its own.
Other things we're doing are changing or pulling out NPCs in key locations to help even out the balance of time and effort each side has to take to push through. As well as some minor changes to locations that people find are easily exploited to advance faster.
We're shifting some of the honor from the earlier NPCs, that help make AFKing so lucrative, to the end of the battleground and more for actually winning.
The graveyard spawning is being changed so that players aren't sent back to the cave unless there is nowhere else to spawn, which should help encourage horde to play a bit more defense if they're being beaten back.
And we're also correcting the ... I think Jeff referred to them as "creative pulling mechanics" with the general's.
Everything together, we feel, should help encourage players to participate, while also improving overall balance.