Android 4.2.2 released for Google Nexus devices
Download links are listed below if you can't wait for the OTA. Updates for the Nexus 4 and 3G Nexus 7 will probably follow over the course of the next few days.
Nexus 7 WiFi (nakasi)
Nexus 10 (mantaray)
Galaxy Nexus (takju)
More details on what's new can be found here...
Your device needs to be running the JOP40D build in order to flash the updates, doing so from another build will probably just fail, but we wouldn't attempt it either way. You'll have to use the side-load method in order to install these updates if you're running a stock ROM, and that means connecting to your PC via USB and using the command line. If you're unfamiliar with with how to do this, we probably wouldn't suggest trying it in the first place.
The short version: get your Nexus 7 or Nexus 10 into recovery, hook it up via USB, and select "apply update from adb," then use the 'adb sideload [FULL UPDATE FILE NAME HERE]' command. If you have a custom recovery, you should be able to apply the update in the normal way (straight from the zip file on device storage). For detailed instructions for the Nexus 7, see this post