Not as much as you may think. Maybe in ZA because there was no mass market console before the Playstation, but Nintendo gave out some really interesting stats about a year ago, when they announced the Wii (nee Revolution).
Although there's been a lot of games consoles sold the size of the gaming market has not actually increased significantly for around 10 years. (~80 million gamers I believe) It has also polarized as a male dominated activity in those past 10 years, which is why Ninty changed direction in such a big way, it wasn't just to hype 'their' approached, they had the numbers to back it up.
Sony needs to remember, that
a.) When you're on top, the only place to go is down,
b.) People like to back the underdog.