Sony today announced that PS3 software update v4.2o will be released tomorrow, “which will include a few minor updates in order to strengthen functionality and improve your overall experience.”

Update v4.20 will improve sidetone audio in your headset with a new option to “select one out of five levels for microphone audio, or turn the feature off completely.” Sony also says this update will enable virtual surround sound functionality, giving a superior audio experience to those who use the Wireless Stereo Headset to watch Blu-ray or DVD movies on the PS3.

In v4.20, you will be also able to set a timer to automatically turn of the PS3 system for [Video/TV/Music/Photo] and for [Game/Other Features].

The update also bring improvements in saved data management by allowing you to “select multiple saved data items and delete or copy them as a group.”

(Playstation blog)