Google has now pushed the Android 4.2 Jelly Bean source code to the AOSP (Android Open Source Project). The SDK platform is now available to developers, so hopefully we will see some custom ROMs based on Android 4.2 appear in the not too distant future.
The SDK includes access to a number of features including interactive lock screen widgets, a ‘Daydream’ interactive screensaver mode, support for external displays and native RTL support. We do hope that Sony received the PDK prior to this and is already hard at work optimising Android 4.2. Time will tell.