Demon's Souls is essential. I don't think it is overlooked though. I find it to be more intimidating to many people since it has a very steep learning curve and the harsh and unforgiving nature the game holds towards it's players. I retired after New Game++++ and it is my favorite game of this...
I finally saw Swans last night and it was the loudest show I have ever been to. Michael Gira is the type of artist that only comes around once a lifetime.