Google has started updating the GSM Galaxy Nexus smartphone, as well as the Nexus 7 and 10 tablets, to Android 4.2.2 Jelly Bean build JDQ39. Details on what’s changed are vague, but we imagine the update comes with a host of bug fixes, performance improvements and a sprinkle of enhancements. In fact, the Nexus 10 update prompt specifically mentions stability and performance improvements. Users should expect the upgrade to hit their respective Nexus-branded devices over the next few days to a week.