I've played a fair bit of Demon's Souls in the past, I do really love the gameplay. Both games are really huge time syncs though right? I'm asking which should I play if I only could only play one or ther other.
Oh, then Dark Souls. More active community IMO, and the game will probably be closer to DS2 mechanically. Imbask is on the money in that a playthrough can be pretty long if you dick around. Took me 70hrs* my first time through.
*
I'm really bad at the game.