Google has released the factory images of Android KitKat 4.4 for compatible Nexus devices. If you’re waiting for Google to roll out the over-the-air update, then this is the right time for you to download the factory images and flash your device by yourself.
Android KitKat 4.4 is not compatible with the original Galaxy Nexus. But some sites report that the Texas Instruments’ SoC is outdated and the official support has been stopped, which appears to be true. The KitKat might not look like a major update to Android devices, but the review from Ars Technica would explain you almost everything that is completely new and exciting in Android KitKat.
Moreover, Google has also posted detailed steps on flashing your device the right way with the latest Android KitKat. Here are the links for the factory images: