I guess here is why I'm drawing attention to the wealth problems with the Parcel system...
Game balance expects PC's to have a certain amount of magic items (and money to spend on more, or potions and rituals) - and in
4E, this aspect of the game is managed by the Parcel system. From that perspective, the DM can create treasure and magic items for a series of encounters, literally in minutes.
BUT - in an old school megadungeon, you'd go by things like the % in lair, the treasure types and charts (haha, remember treasure type "Q", stuff like that!)
If you built a level 1 dungeon with 50 encounters, you literally could give every monster an appropriate treasure. And one reason players might not spend time on level 1 any longer is the XP and Treasure rewards they're getting no longer keep them moving forward at an acceptable rate.
In the
4E paradigm, I don't believe XP is exponential any longer... it's a more gradual curve... raising the issue that a level 2 party could still be advancing at a decent pace while whomping on level 1 monsters.
I guess I see the Parcel and Encounter level, XP per encounter, and Dungeon level issues are a bit intertwined. In a normal dungeon - guess what - you've beaten all the encounters, time to go down to the next level. Harder to do in a megadungeon where there are more areas of the current level that could be explored.
Not ready to say
4E is a mess (yet) because we love the game play and I love the behind the screen aspects of it, but the gentler XP curve may cause some problems in the megadungeon environment.