"Next gen gameplay" to me sounds like a game playing better than its predecessor to the point where it makes it feel outdated. Like SMW compared to SMB, or GTA5 compared to GTA3. The core is familiar, but so many changes (usually for the better) have been implemented beyond just the graphics. Some of the SS reviews make it sound like SP didn't do much to change the gameplay or structure of the game at all. That can be a double-edged sword.