I'm also looking to run a Dark Sun games.
So far I have nothing huge planned, mostly just doing stuff that ties into the world which includes:
Doing some caravan duty, dealing with ambushes on the road and the like.
In the event the party decides to leave the path there are other wilderness encounters that fit will in the desert area. (One I particularly want to do after reading through the creature compendium is the "vultures" which would either join a fight midbattle or attack soon after another fight as they try to pick off the weak, etc).
At some point, there will likely be a gladiatorial games portion where the group takes part in some arena fighting, (I especially want to make use of the rules from a while back that have a skill challenge for getting the crowd on your side and includes a "rioting crowd" as a massive swarm, lol).
And then, of course, there is some in-city intrigue around the sorceror kings and the like, and if they do some desert exploration they can end up in a good old fashioned dungeon delve (with a bit more of a time limit thanks to the provisions system of Dark Sun).
I have to see what kind of characters the players end up coming up with. If it's primal and arcane, with the arcane guys leaning towards preservation that will likey focus the overall arc towards that conflict, for example.
I'll keep an eye on the thread to see if anyone has any ideas I can steal
