I spent most of my play time today getting side-tracked through a new area that was just opened to me. Made me realize the main difference between Borderlands and Dark Souls (well, it's obvious, but it's interesting when you think about it more deeply!): fetch quests vs the environment being its own quest.
In Dark Souls, progress is its own challenge, and has its own rewards. Your discovery of one area leads to the next and you progress, not only for progress's sake, but for the discovery. And the bosses! But in Borderlands, you progress because some NPC told you to go there, and gather this or do that, then come back and have him tell you where to go next. To be honest, it's when I get side-tracked that I enjoy Borderlands the most! I like discovering the environment through exploration, and curiosity, and have the environment be its own quest. I love finding hidden treasures, not have some NPC tell me "there's a treasure there, get it and I'll give you some loot as reward."
Seriously, *** fetch-quests! If there's one thing devs need to learn from From and Dark Souls, it's that you don't need to have dumbass quests to lead the player through the game; let the world do that. And then you'll have your fanbase poring and puzzling and piecing together its lore themselves!