While Microsoft has criticized Sony for making Blu-ray standard on the PS3, Ray Maguire of Sony UK has replied, claiming that it is essential to the next-gen gaming experience.
"Blu-Ray is really important for the games side of our business because what it does is it give us the ability to have 50Gb of information actually on the disc," Maguire said.

"With PlayStation 3 you're looking at a Cell chip that has immense computing power. That means you're going to need a huge amount of storage as well - we really need that Blu-Ray disc because what we don't want to be doing is swapping discs half way through loading. It's really important to us."
It's going to be interesting to see what game developers can do with Blu-ray. If you'd like to read more, the entire article can be found here.