You need to keep an eye on this Sony Mobile forum thread where all of the kit numbers that receive the update will be posted. You can find your kit number by accessing the service menu on your handset (type *#*#7378423#*#*). Then hit Service info > Software info and look for the ‘Customization Version’ of your Xperia. This update will only take place via your PC or Mac, so there will be no OTA option.
The rest of the Xperia line-up including the Xperia arc, Xperia PLAY, Xperia neo, Xperia mini, Xperia mini pro, Xperia pro, Xperia active and Sony Ericsson Live with Walkman will start to receive the ICS update from late May/early June as per the previous schedule.
Via Sony Mobile.