The most important aspect of LDON was that everyone who participated in a successful mission got points. Everyone could use those points to buy something marginally useful to them, and in some cases depending on the players advancement, they could buy something hugely useful to them.
This aspect of it was one of the best MMO idea's I'd seen. Now granted it wasn't implemented perfectly, but I saw glimers of what it could be, and it could be huge.
Think on the basic reasons why grouping occurs. Obviously there are the social aspects of it, but beyond that it basically boils down to grouping for a selfish reason, hopefully while achieving a larger objective. The selfish reason can be xp gain, or possible loot gain from the camp being attempted, or loot gain from a quest drop being obtained. The only above reason that is guaranteed to be achievable by every member of the party is the XP gain. Obtaining loot or completing a quest is rarely achievable by more than one party member at a specific camp. So you end up with a group of 6 people (best case) and of the 6 only 1 is hopefully going to increase his characters power through a new item, the other 5 are just along for the xp, with hope that at some point it will be their turn to have an item camped for them. Which may not happen if they don't have good friends, or may only happen once every few weeks. Of course this is talking about 1-group stuff, raid stuff is different.
Compare this to the LDON model. At the end of a 45 min mission, EVERYONE in the party added to their point total for that camp, possibly allowing them obtain an item they can use to increase their character's power. EVERYONE sees advancement, even if the actual frequency of loot gain is comparable to doing it the old way by camping items and rotating who gets the loot.
Additionally the built in timer was awesome. It guaranteed that a session was not going to take longer than 90min, no matter if you succeeded or failed. This is great for those who have very short playing times, combined with the ability to quickly gain access to correctly leveled experience mobs, it made EQ much more casual gamer friendly.
I've not played on WR long enough to compare WR to EQlive, I'm just bringing up some points that I thought were very nice about the LDON expansion. Yes the dungeons sucked, but who says you have to use them? You like Seb/Guk/SolB so much, figure out how to spawn instances of them!
One more thing I loved LDON for.... it _forced_ people to dungeon crawl because of the lack of respawn. Dungeon crawling is fun. camping one spot for hours and killing the respawn is not.