The Tourtured Champion - Yogg-Saron tells us ""He will learn... no king rules forever; only death is eternal! this same line is repeated by Mr Tenereas himself in the 3.3 ending Cinematic. Some also speculate that the "death is eternal" implies Deathwing himself.
The Creation of the Dragon Soul - Dragon Soul Creation. What do we steal in 4.3? Yogg-Saron tells us "His brood learned their lesson before too long, you shall soon learn yours!" The Black Dragonflight are all but extinct now, or it is implied. "you shall soon learn yours" could imply the upcomming war between the Alliance and the Horde. And in many ways the arms race between them.
The Assassination of King Llane - Yogg-Saron tells us "A thousand deaths... or one murder." Could this mean that he is implying that if we kill a faction leader the war will end? I originally thought that this meant Varian was going to die, But then again with the upcomming "Varian is Alliance SUperstar" quest could this mean Garrosh? I mean the vision involves an orc. But maybe, The roles have switched? Then I came across this "Your petty quarrels only make me stronger!" Now. Did the Hour of Twilight actuallly fail? Or was it the Old Gods plan to create a full-scale war between the Horde and the Alliance.
Death- Yogg-Saron tells us "The end of days is finally upon you and ALL who inhabit this miserable little seedling", This is just implying the Hour of Twilight.
Sorry about any spelling mistakes. Was in a rush.