They've probably been contacted by Blizzard and asked not to reveal the ending cinematics just yet.
SPOILER
Anyway, it was something like this - Imperius and Tyrael watch as Malthael falls dead, killed by the Nephalem. Our hero in glowing and Tyrael says that he saw him in a different light, knowing that he can defeat the greatest champions of both Heaven and Hell. Tyrael is afraid the the Nephalem will one day become corrupted and that he'll become the undoing of all things.
Tnx a lot!