The update weighs in at around 200MB, so using Wi-Fi directly or syncing with your PC are better options than updating over your carrier's cell network.
Xperia S owners will receive a notice when the update is ready. The rollout will run over the next few weeks, so Sony cautioned that availability will vary depending upon the carrier.
Beyond providing a bite of Ice Cream Sandwich, Sony is bundling some new media apps as part of the update.
A Walkman app taps into social media by letting you share your favorite song tiles with friends. Facebook integration now helps you download album art, artist photos, and other information from Gracenote. An Album app offers photos and videos that you can share through Facebook.
And the Movies app displays films in high-quality format while providing a searchable database with movie posters and other information related to the content you watch.