Image courtesy of XDA user holeindalip
In AT&T's official blog post, the company outlines what users can expect post-update, including "key enhancements to the user interface, battery efficiency and processing speed." The post goes on to describe some of the visual changes with KitKat's interface, along with other 4.4 goodies. Oh, and LG decided to make Knock On less janky in this build, too. So that's good.
The update is rolling out now, so hit up the About > Software Update menu to grab it.