Hopefully this Garrosh raid will be a perfect lore excuse to finally get rid of Thrall along way as well. As noble sacrifice or for some other reason, doesn't matter. Really expected him to be gone during Staghelm's assault or that he will sacrifice himself as a key to defeating Deathwing. Also for years being Warchief of the Horde and for being World Shaman, that orc didn't get enough money to learn how to use at least fast ground mount, and in Hour of Twilight it looks like he doesn't even have any mount in possession anymore at all, becoming just a burden.
Sorry, I just don't like orcs. Still Garrosh raid has no right to exist unless there will be some "Madness of Thrall" kind of encounter, where we will have an opportunity to finally free world from that sneaky orc once and forever. Aggra could be included as bonus encounter or heroic mode feature as well.