What would be good is if the game could install as you're actually playing it. I don't know if that's even possible, but it would be cool.
The 10 minute example was with Devil May Cry 4, so I would also doubt that every game would take the exact same time to install and offer the exact same reduction in load times. According to Joystiq, DMC4 takes up 4-5GB of disc space when fully installed, so some games would be bigger than that and others, Ninja Gaiden II for example, would be smaller.







