Sony Ericsson has outlined the upgrade path for their Xperia line of devices. Android 4.0 will come to their entire 2011 line of Xperia devices. The upgrade is scheduled to start around the end of March or early April 2012. The roll out will be phased out across products and carrier. So you may not get the update by the end of April.
The first Xperia devices to get the update will be the Arc S, Neo V, and the Ray. Then, around early May, you can expect the Arc, Play, Neo, Mini, Mini Pro, and Pro devices to get the update. Keep in mind, this is only for 2011 Xperia line of devices. So any X10 owners are out of luck.
This announcement seems to have very similar time lines to what we heard from Samsung earlier. It seems like ICS won’t be ready for existing devices for another 3 months – even if leaked copies of the ROMs are currently floating around the internet.
(Source = Slashgear)