Really not too much to crow about...improved gallery...a few improvements to Blinkfeed...Do Not Disturb. Feels a lot more like a minor update.
Strangely, it seems as though ART is completely missing. At least I can't find the option to switch from Dalvik in the developer settings, like I can on the Moto X. Go figure.
It's been fairly uneventful so far. Probably the update I like the most are the improvements to the Gallery. A bit more customization in Blinkfeed too.
I got mine last week I think. Change in the icons in the notification bar. Gallery, and also Browser seems different but can't tell because I never use the stock browser.
When my brother first got the update, battery life was horrible, but after a factory reset it appears to be better than before the update. I'm hoping this is a common theme for kitkat.