With FFXIV’s v1.6 patch not to far away (March 3rd), players will be finding a number of new side quest and changes that will make questing smoother and easily grasped. Local level quests will also be updated in much the same way.
Sidequests are a new category of quests that are being added to the game. These will be made available through various NPCs located in each of the three cities, given that a player first fulfills certain class/rank prerequisites. The content of these endeavors vary greatly from one another, and we will continue to add further sidequests in future patches.
NPCs offering sidequests are easily distinguishable by the presence of an exclamation point (!) icon above their heads. The same icon is also displayed at sidequest NPC locations on the map and minimap. In the future, we plan to extend this feature to other quest NPCs, such as those offering class quests.
Read more here.