Downloaded the KitKat update on Friday. Video gives a few thoughts. Really happy with the ability to use AC Display now. Antutu benchmark scores are better than ever.
Google's 4.4 Kitkat Info: Android - 4.4 KitKat note all of the stuff for the Nexus 5 only * :-(
AC Display Thread: [APP][4.4+] AcDisplay | v1.2.5 | 19.02.2014 - xda-developers