Explorer

This Racial replaces:

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• Find Treasure
  Allows the dwarf to sense nearby treasure, making it appear on the minimap. Lasts until cancelled.
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Which was relatively useless in Burning Crusade and Wrath of the Lich King simply because of the lack of meaningful treasure in the world to track.
Explorer itself has gone through a bit evolution on Beta as well, first it was:

• Archaeology skill increased by 15 and you survey faster than normal archaeologists.

And after Beta build 13221 the skill increase got removed and turned into:

• You find additional fragments when looting archaeological finds and you can survey faster than normal archaeologists.

This change was most likely due to adverse effects the skill increase racial had on how Archaeology works and turned out to be a handicap instead of a bonus. Mainly because you stopped gaining skill points from Surveying at 100 (for dwarves aswell), Dwarves reached that skill level earlier and their 15 additional skill points got lost when other races caught up while going to 100 without solving any Artifacts which was the sole skill gain after 100. This would only nullify the skill increase but to make matters worse to obtain achievements such as Journeyman in Archaeology, Master in Archaeology, etc. and even Realm First! Grand Master Archaeologist, Realm First! Illustrious Archaeologist a Dwarf needed to continue an extra 15 skill points above the achievement goals to obtain it because Racial skill increases aren't taken into account on achievements.

Unlike all other Profession bonus Racials this can be useful to every Dwarf because Archaeology is a secondary profession.

Like the spell aura hints at, Dwarves get 15% additional Fragments, this was not active on Cataclysm launch but was a few days later changed with a Hotfix.
On a successful Survey any max skill Archaeologist can get either 3 or 4 or 6 Fragments (never 5) this gives an average of 4.33 Fragments.
For a Dwarf this +15% turns that into 3.45 or 4.6 or 6.9 Fragments but because the Fragments are looted as items this is rounded to the nearest integer, in the case of a Dwarf that gives 3 or 5 or 7 Fragments (never 4 or 6) giving an average of 5 Fragments per successful survey.
This rounding makes Explorer slightly stronger than the Aura implies, 15.38% additional Fragments.

The faster Survey for Dwarves is not reflected in the Ability tooltip and simply states 1 sec Cast like any other race but Survey for Dwarves is in fact 0.65 sec (the aura simply subtracts 3500 Milliseconds to the cast). This shorter Survey time gives no real noticeable benefit because of the 5 sec cooldown though.

Perhaps Explorer is best compared to Human Diplomacy instead of the other Profession racials. Both apply to a grind that has a final goal and once reached both racials become useless, fully completing Archaeology no doubt takes longer and is more "painful" than maxing all the useful factions but getting some Reputations is required because of gear enchants while Archaeology still is purely optional because of the removal of Path of Titans that was supposed to use Archaeology as it's driving force.
For somebody going after the Professor tittle from It Belongs in a Museum! this Racial is certainly an asset just like Diplomacy is for people trying to get Insane in the Membrane.

This racial provides 2-3 more fragments from both digs AND crates, and removes the cooldown from the survey spell.

I find the cooldown on Survey to be utterly annoying. I have no idea why it HAS a cooldown, but if it's related to some mechanic, 3 secs would be good enough.