Yesterday Android 4.4 KitKat was officially out and so is the ASOP for android-4.4_r1 (KRT16M) and so is the factory images for “hammerhead” for Nexus 5 (GSM/LTE) and so is the next API 19 SDK update.
Also there is the new JBQ: Ed Heyl
here is link for android builders: https://groups.google.com/forum/#!topic/android-building/JVLaFRoJxFk
here is the changelog: http://web.djodjo.org/article/download/android/changelog/changelog_JLS36I-KRT16M
factory images and insecure boot image + deodex system can be found here: http://web.djodjo.org/article/download/android/ROM_images/factory-images-nexus5-hammerhead
detailed list of new features: http://developer.android.com/about/versions/kitkat.html