Talk to Krag directly southeast of the Danak Shipyards in Jarsath Wastes. He is a big pile of rocks on the ground in an underwater cave ( -857, -54, 1291 ) .
You get an info window when you mouse over it. All group members must do this at the same time in order to get the next update. If you don't you'll need to go back and get another keg to place.
When the keg explodes 5 heroic titan shards (level 79^) will pop. Kill them for update.