The difference is not dramatic, but it is real.
StreetFighter4 runs at 60 FPS with quite precise details held 30 to 50 with the details to a minimum or absent. CPU, disk (swap) and RAM are less stressed, so we can run more programs.
I noticed the difference is networked: GTA4 multiplayer not complain over the lack of resource.
So games, take on another dimension. The display is thinner, the scenes are fluid and rediscover the network or another brings games to life.
I'm no gamer (even less hard-gamer), my games were 3 or 4 years, and now they are fluid and network with the child, it's like rediscovering our games.
Very good HD video or office