Raven Software has always been one of my favourite developers. They have a simple approch to video games and haven't changed that much to suit the industry. That is, making action-focused games that are simply fun. Never epic, never more than ten hours, but always enjoyable.
With Wolfenstein they've tried to integrate some of the things that are becoming common in action games; collectibles, upgrades and a non-linear approach. But it's only done to a small degree. At it's core, Wolfenstein is still just a fun first person shooter, and that's all I was really hoping for.