Each Boss in heroics now drops 1x Emblem of Triumph
The first time you complete a random heroic each day you get 2x Emblem of Frost and 26g
Each further random heroic you complete gets you 2x Emblem of Triumph and 13g
You can do as many random heroics each day as you want, even repeating heroics you have already done, but only if you use the random dungeon feature.
You can trade Emblems of Triumph for Emblems of Conquest in the sewers in Dalaran.