I don't really understand all this apparent clashing of opinions regarding difficulty. I always thought, if you died a lot while playing through a game, that meant it was hard. What is all this redefinition of the term? Dark Souls isn't hard, it's cheap. A game isn't hard if it kills you to teach you, that's just trial-and-error gameplay. A game isn't hard if the enemies are just damage sponges. A game isn't hard if there is a way to survive every encounter, you just need to play careful.
Then what does make a game hard? How exactly is Dark Souls not a difficult game? I find it to be hard. I'm only part way through it right now, but I've died scores of times. I keep running into sections that I can't find any way around because the enemies there kill me every time. Every new section of the game I reach has the potential to stomp me flat because I wasn't ready for it or I don't have the levels and equipment for it. This sounds like "real" difficulty to me.
That said, I have remarked to myself that I don't think Dark Souls is a "cheap" game. You do die a lot, but so far almost every death I have suffered was my fault. The game doesn't manufacture deaths for you out of nothing, it just doesn't allow you many mistakes. If you fuck up, it lets you know it immediately. But only a couple times can I remember dying because of something that seemed wrong or unfair, and those were isolated incidents due more to graphical glitches than the design of the game.
I don't even like really hard games, usually. I hate losing, and I just get mad when I screw up and die, it makes me feel stupid. And I do not like Demon's Souls at all, that game is just too hard and too unforgiving. But I am loving Dark Souls so far, because it does difficulty right. It doesn't cheapen your deaths, and each death can teach you how to avoid it next time. When you die, you don't lose too much progress, and when you succeed, the feeling of victory is delicious. Unlike Demon's Souls, these victories are numerous enough to make it feel like you are advancing in the game, rather than slogging through the same long section again and again for one measly moment of triumph before another wearying trudge through certain death.
I'm loving the game so far, and it's all down to the design hitting the sweet spot between real, fair, and balanced difficulty and opportunities for sweet success.