Sony has confirmed that they will be releasing the Android 4.1 Jelly Bean update for their 2012 Xperia lineup by the first half of 2013. The Sony Xperia T, Sony Xperia TX and the Sony Xperia V will reportedly receive the Jelly Bean update as early as the first quarter.This will be followed by updates to the Sony Xperia S, Sony Xperia Acro S, Sony Xperia Ion, Sony Xperia P, Sony Xperia Go and Sony Xperia J. However Sony has still to reveal a time frame for these devices to get Android 4.1.
Unfortunately Sony is not planning on bringing Android 4.1 to their older 2011 Xperia lineup. While we do understand that supporting such a wide lineup of devices isn't practical, its disappointing that they wont benefit from the performance improvements of Jelly Bean.
Sony has been very generous with their Android updates, especially compared to their competitors. But we have to respect their decision and hope that the developer community to be quick to port Jelly Bean over to those older devices.
source – Sony