very good question !
As far as i'm concerned ,i wait what KK generally have promised : a lighten and optimised system !
And the big surprises ( no found news about ! ) :
what will it change ???!!! ( how will be the interface ,Touchwiz ...etc ...)
what's the innovation ??? it's a simply kernel&system smalls changes + the previous 4.2.2 touchwiz and parameters ? or it will be totally different ?
I wait less baterry consomption too !
But i'm not ready at all ,because i don't know if this KK will have root ASAP , and i prefer to wait a fabulous custom kernel for still more performance&less battery consomption .......
.an maybe a deodexed/zipaligned version too .