First I want to say WOW...I love how these open discussions end up with amazing ideas and also feedback from the community.
We said many times that the community will play a huge role in our project and that is why we value every single comment.
So to the point about how I imagine the journeys. I really want to get away from the "go to the npc with an exclamation mark, get the quest, slay 5 chickens, go back to the npc". Personally I imagine them like a real long journey, maybe we can make it every 10 levels. You start the journey let's say at level 1 and you complete it at level 10, you also complete the zone in which the journey is and get a bunch of cool rewards, maybe a title etc... During the journey you explore the whole zone and follow a story, doing different stuff and gaining exp and small rewards, also learning new stuff from the NPC's you meet. The other thing I imagine is every class / race combination has its own unique 5 journeys (till you reach level 50). Of course you will say "How am I going to be able to play with my friends?" Well you will have the ability to join one other's journeys and combine them so you can level up together. I want to say that this is in my mind and I am telling you this for the first time, I haven't talked to any ody about these ideas, but I think this could be a nice concept, it needs work of course and I'm not sure everything is doable but this is how I imagine it.
Now for the player made tasks or whatever we will call them, let's say you have a main role in your guilds raiding party and you go to raids very often, you barely have the time to let's say collect mats for crafting, that is when you put up a task for gathering mats and you offer items/or a little amount of gold, cuz you don't have the bigger amount of gold asked at the market. Or you need help with a bunch of hard mobs on your journey, that's when you hire someone to come and beat them for a certain price. You can think of yourself as an employer.
For the question about what's in it for the people who take on the tasks except what the other will give them, well we can make an achievement for certain amount of tasks made, we can throw in even a title, everything is open for discussion and can be made.
With this functionality we will engage the players to help out strangers. Everyone is been in a situation where all your friends are offline and you are stuck at some point and can't do it by yourself, start writing in the global channel for some good fellow who will come to aid but you spend hours in searching for that one guy who will come and do it just because he is a nice guy.
Now I thought of something else, we can make it with information also, you need something to know and can't find the knowledge, well put up a task for let's say 20 gold and someone will come and tell/show you what you need.
This is getting very long so I stop here. I must say it again this is my own concept about the things and I'm eagerly waiting to know what you guys think and also the devs cuz they are hearing it for the first time also.