Some of the new features of the update include: xLoud - a boost for your music when it's played through the phone's speakers, Stereo recording - the ability to shoot video with high-quality stereo sound, Digital home - the feature to let you stream content from your phone onto DLNA devices, and some new themes and a landscape mode for your home screen.
The update is for Xperia Arc and Xperia Play phones, and it's not available to everyone yet but it should be rolled out to everybody within the next few weeks (though there will be certain markets excluded from getting this update). Check for updates by going to Menu > Settings > About Phone > System Updates or connect the phone to your computer and run the PC Companion software.
source: Ubergizmo
