#1 - Nov. 1, 2011, 11:41 p.m.
Upon the FIRST time you play Diablo III, the following happens only ONE time at the start of your questing on your FIRST character:
When you go to New Tristram for the FIRST time on your FIRST character, an "!" quest marker shows up where there is no NPC on the Mini-Map.
When you walk up to the "!" in the Mini-Map, the moment you walk into view of that exact spot in the regular map, the "!" vanishes from the Mini-Map. Walk away, come back, repeat, keeps happening.
It's not until later that you find out this mysteriously glitched "!" is actually for the quest "A Shattered Crown" objective of "Return to Haedrig in New Tristram" which then makes the NPC "Haedrig Eamon" appear so you can take the quest and know where the "!" was coming from.
In summary, the "!" quest indicator shows up too soon in the player's mini-map, for NPC Headrig Eamon, prior to quest or NPC availability, but only for the 1st character's 1st time running through the game.