Well, I just got the new issue of Dungeon in the mail and did some scouring of my own in Life's Bazaar... I found these interesting tidbits:
All rogues in the adventure have a Special Quality called "trapfinding". This seems to be the new name for the Traps ability in the PHB that allow rogues to find traps with Search.
Additionally, a level 5 rogue has the Special quality "trap sense". I think this might allow a rogue to automatically get a chance to search for trap when passing within 5 ft., just like the general elven ability. Perhaps this was implemented to speed up games so that rogues wouldn't always be spending time searching for traps. It could also be something granting rogues bonuses to saving throws to avoid traps, like the high-level uncanny dodge stuff.
A character who uses a whip gets their whip attack listed as follows:
+6 melee (1d3+1 subdual and trip attack, +1 whip)
This seems to imply that one can now use a whip to both deal damage and trip during the same attack. Whip still seems to require an exotic weapon proficiency. No way to tell if the problem of whip being a small weapon and thus being very disadvantaged in making disarm attacks has been fixed, but the adventure does list disarming under the character's tactics.
There is a non-ranger character listed who has the feat Two-Weapon Fighting, but this does not have the expected effect on his attacks. His attacks are listed as follwos:
+4 melee (1d8+2/19-20, longsword) or +0 melee (1d8+2/19-20, longsword), -1 melee (1d6+2/19-20, shortsword)
I should mention that this character has Weapon Focus (longsword) explaining his extra bonus with this weapon. Other than this, however, this character receives no off-hand penalty but receives a -4 penalty to both attacks even though he uses a light weapon as one of his attacks. Additionally, he gets his full Str bonus to damage with each attack. It seems that Two-Weapon Fighting now grants the old benefit of Ambidexterity (no -4 off-hand penalty) as well as allowing full Strength bonus to the secondary weapon, but does not grant the reduction to -2, -2 as in the 3.0 version of Two-Weapon Fighting. Or perhaps that bonus is only given for using a light weapon in both hands?
An illusionist has as his forbidden schools Conjuration and Necromancy. A transmuter has Conjuration and Enchantment. Either 3.5 requires stiffer forbidden schools or Conjuration has been reduced in power as a forbidden school, or both. Even if conjuration were reduced to the level of medium-weight schools like illusion and enchantment, however, its hard to see it not alone off-setting taking Illusion as a specialty school. A mandatory two forbidden schools may well be implemented.
A gnome has listed under his equipment a "gnome-sized dagger" (which deals 1d3 damage) and a "gnome-sized light crossbow" (which deals 1d6). This could well mean that the double-listing of halfling and normal versions of weapons is at an end, just having clear rules for making smaller weapons in the PHB. Or this could just be something done for this adventure, since these weapons arent given in the PHB as is.
The phrase "automatic reset" is included at the end of most trap listings. One trap has "manual reset". It seems that how traps reset may well be included in 3.5 statblocks. A spiked pit trap does not have any reset information, which seems to imply that if the trap doesn't reset, this information is not given.
A rat familiar has a Special Quality called "minor scent". I'm guessing that this is a reduced version of scent availible to familiars. Familiars can probably not track with it, thus avoiding the problem of wizards acting as rangers and using their familiars to track.
An ogre character has the feat "Martial Weapon Proficiency (two-handed melee weapons)". This seems to mean that characters now get a partial set of martial weapons by taking the feat, rather than just a single weapon.
A dwarf character with a half-troll template has the following special quality:
+4 bonus on saves to resist bull rushes and trip attacks when standing on ground
Could this be a new dwarf ability, or is it an oddity of the half-troll template? Also, will there be saving throws involved in the above two actions or is the term "save" erroneous? Why isn't it just "checks"? Also missing are some dwarf abilities, but the adventure does say the qualities are "summarized". Still, no bonus to finding stone traps is given, which may just be a victim of summarization or it could be left out of the 3.5e dwarf to make room for the urgosh (as has already been reported) and the new resistance to bull rush and trip. No bonuses to hit goblins and orcs are given either.
The above creature also gets a special quality called "improved reach (10 ft.)", which gives him 10 ft. reach even though he is Medium-size. Could just be an oddity of the template or Fiend Folio (from which the template is taken).
The transmuter has a "crystal wand of magic missles". I have a feeling "crystal" is just for flavor and has no rules implications, especially since other wands have no descriptor, but it could be that crystal wands are special in 3.5e.
Anyway, this is what I found that hasn't been mentioned already. Hope it helped.