There have been various reports from both Brazil and Malaysia that new Nexus 4s are shipping with Android 4.2.2 Jelly Bean on-board. There’s no changelog of what the Android 4.2.2 update consists of, but it appears only to be minor bug fixes.
There are upwards of 1000 Nexus 4s produced by LG’s phone factory in Taubaté, Brazil that are running Android 4.2.2 Jelly Bean.
Similar occurences are happening in Malaysia, with 8GB variants of the phone coming pre-loaded with Android 4.2.2 Jelly Bean. There isn’t any noticeable difference at the moment from other Nexus 4 devices except for the “dev-keys” written at the end of the build number.
This could just be a minor error made by the manufacturers, or a private build that wasn’t supposed to be released. We’re going to have to wait for an update from Google themselves to clarify the situation. Who knows, maybe all Nexus 4s will be updated to Android 4.2.2 Jelly Bean soon.