That is a plus, and I do see the appeal to MMO's. But I also see the appeal to the television series, Mad Men. What do these two things have in common? They bore the crap out of me!
It feels like no matter how they doll it up, all those games have pretty much the same combat system. Doink 40 dmg, doink 40 dmg, doink CRIT 100 DMG!!!! doink 40 dmg, Vibrant Radio Demon was defeated! 500xp!
Plus the whole lack of an ending thing never appealed to me. "100,000+ hours of gameplay!!!" is not a selling factor to me. I like the satisfaction of saving the world and seeing the credits roll. Its why the Diablo games have always held my interest. Bloody, intense, very satisfying fighting, serious dungeon crawling action, has an ending.