Jean-Baptiste M. “JBQ” Queru has announced that Android 4.2.2 Jelly Bean has been officially released into the Android Open Source Project along with the matching proprietary binaries. The release of the source code started soon after Google released the 4.2.2 firmware images for its Nexus devices, however Queru's announcement confirms that the push to the AOSP has been completed.
Along with the source code, which is tagged as build JDQ39, the binary drivers have also been released for the different chip sets (like the Wifi and NFC chips) used in the Nexus devices. Through the Android Open Source Project Google releases the source code for Android, however some chip sets need proprietary binaries. This means that the chip maker doesn't release the source code but has released a driver, akin to the drivers installed on a PC for a graphics card or a network card.
This is the first time that all the Android 4.2 compatible Nexus devices have all the matching binaries available in AOSP. This is particularly great for Nexus 4 owners since 4.2.2 marks the first release of the binaries for that device. It is also the first time that the drivers have been released for the 3G version of the Nexus 7.