According to the PS Blog US, a new system software update version 4.20 will be released for the PS3. This update comes after the recently release 4.10 update (that I forgot to cover, it must have been a little under the radar).
4.10 improved performance for the already existing PS3 Wireless Stereo Headphones, specifically the ability to hear your own voice in multiplayer games (sidetone as it is called).
Based on your comments at the PS Blog, system software update (v4.20) will improve sidetone audio performance by giving you the option to select one out of five levels for microphone audio, or turn the feature off completely.
For those of you who use the Wireless Stereo Headset to watch Blu-ray or DVD movies on your PS3, this system software update will also enable virtual surround sound functionality, giving you a superior audio experience.
Also in the coming update is the to to set the amount of time that the system will wait before turning itself off automatically for [Video/TV/Music/Photo] and for [Game/Other Features], and you will now be able to select multiple saved data items and delete or copy them as a group.
I'll post an update tomorrow when the firmware goes live, so stay tuned.