Quoting AlLanMandragoran,
Awesome, and shout out to Heavenfall for being the first to recommend this awhile back. And holy crap, it got put in fast. Well done.
It's hard to root through the oldest threads, but I'm pretty sure this maiming idea came up long before the first beta--it was around the time several of us were talking about related things like wanting to have the maps reflect the game history with things like labels (Field of a Thousand Skulls, that sort of thing) and wacky ideas like mass battlefields becoming resource nodes for necromancy.
I have to agree with the folks who find the 'automatic death prevention' side of this function a bit unsatisfying. Even more unsatisfying would be to see magical repairs for these injuries be a common part of the game. Maybe as the result of some serious quests, but if it ends up as just another node on the tech tree that will definitely undermine immersion related to the champions. I'd be OK with that lost ear staying lost.
And kudos for the notion of making the occasional lopped-off bit some form of treasure/spoils for the faction that wins the fight. Part of a powerful spellcaster could maybe be used in forging an important magical device, and part of a renowned warrior could be a non-magical morale booster or maybe affect charisma for a sovereign or champion who carries it.