User blog comment:ShadowPancakes/ZeniMax Online Studios and Bethesda will officially announce Elder Scrolls Online in May 2012./@comment-68.38.139.95-20120318021644

My guess is that if it occurs during the second era, it likely involves killing dragons as Reman Cyrodil's dragonguard. They did just finish fleshing out the whole mythology of the dragongaurd after all for Skyrim