GameSpot has been running a feature about how audio plays just as big of a role in the next-generation delivery of gaming as something as silly like graphics. There are a lot of buzzwords tossed around, but the point comes through clear as a bell: gamers have a lot to look forward to when it comes to what you hear.
The PS3 has the audio processing power to push 512 simultaneous voices or sounds at the same time. Sotaro Tojima (he's the sound guy for MGS4) wants to make you think you're in a movie studio when you hear his goods. That means a slew of environmental and situational audio backed by surround sound. Hope you're ready to invest in more hi-def equipment because it's going to take more than just an HDTV to get the full experience.
Expect to spend around $200 for a quality setup in the sound area.