It's the Witch Hunters. I'm so happy.
Although I wish Dark Eldar would be suddenly but efficiently replaced by the Daemonhunters or the Tyranids.
And here's hoping that you can play different chapters/legions in the game. Blood Angels and World Eaters FTW!
Cleanse. Purge. Kill. -Space Marines
Kill! Maim! Burn! -Kharn the Betrayer
So alike, yet so different.