I've been finding the early Dungeon 1e/2e adventures to be ideal fits for the new 4e ruleset. Curiously, they convert much better to 4e than they ever did to 3e.
In 1e and 2e, you had comparatively fewer magic items and more monsters per encounter. Old classics like Keep on the Borderlands had a dozen or more monsters in "common rooms". Few of these monsters ever owned (or used) magic items, and the classic trove might have a handful of items.
In 3e, *two* orcs were a challenge for a 1st level party. Keep on the Borderlands became a 6th level adventure ("11 bugbears?!? We're in trouble, guys..."), and all those acolytes in the temple of chaos were "supposed" to have +1 maces, 2x potion of cure mod wounds, etc.
...and now 4e brings it full circle again. Many monsters, few magic items. I've been finding that the older modules convert over nearly perfectly. The last couple weeks, I've been running a 2e Dungeon module for low-level characters. It featured, among other things...
* A gargoyle
* A pack of 5 worgs (which became grey wolves)
* A climactic encounter with a witch and 20 goblins (minions)
That would have been nearly impossible to translate easily in 3e. The damage reduction on the gargoyle would have annihilated a 1st level party, and there's no way they could have handled 20 goblins. But in 4e, it's easy to total up the XP for each critter... and figure that they're all pretty much balanced. A 4e gargoyle is 400XP and makes a good (but tough) solo creature for the party. The goblins come in at 25XP each, with the witch adding another 100-150XP. As for magic items, there were 3-4 listed in the entire module, which also translated well. The witch didn't have 3e "level-appropriate" NPC gear; she just had a few random items sitting in her hut. Most 1e and 2e modules are the same.
I'm in no hurry for a 4e adventure path from any of the mainstream publishers, nor do I intend to convert 3e adventures in the near future. I reckon that the 1e/2e Dungeon modules will keep us busy for months.
