I don't think this is an accurate answer.
I, for one, as well as many others, have experienced huge battery life gain. I can easily go until 7PM and still have 25% left whereas prior to 6.1.2, I was having to charge around 7PM under the same usage.
Btw, I'm speaking for my iPhone, not iPad, though I noticed battery is definitely better on 6.1.2 on both devices. That alone should warrant an update. Also, I am experiencing less crashes on 6.1.2 than older iOS versions, namely 6.0.1-6.1.