As you can see from the picture above, it would appear that Deathwing is very much alive still and has plans of his own. The question is, do you think he will appear as a raid target at some point?
Edit:
When the patch goes live, go to the Dragonmaw base camp on Netherwing Ledge (make sure you've done the questline that turns you into a fel orc whenever you're near the Ledge, btw, otherwise you'll probably just be attacked) and stay near Mor'ghor (he's in the main building with an Eredar with him). A "Blood elf" comes up, talks, and then when she leaves, transforms into a black dragon
Post your thoughts in the comments section below!