The Cauldron of Blood, and Bloodwrack Shrine variant, are probably the most welcome updates. Not only was the old cauldron stuck in the 80's, it had very little conversion potential. Looking at these shots I'm bubbling with ideas (mostly revolving using the Khaine statue) Wouldn't that make a great c'tan, or Eldar Avatar? The serpentine medusa also holds some interest for me, namely her potential use in a Daemon army as a Keeper of Secrets or Herald.
The next most interesting addition is the Kharibdyss model. In case you don't know the reference, Charybdis and Scylla were a pair of immortal monsters that Odysseus had to sail between in the Odyssey. Charybdis was a monster that created giant whirlpool that would swallow ships whole, which plays nicely with the Dark Elves niche as seafaring pirates, and monster wranglers. Maybe they'll make a Scylla monster at some point.
More when I find it.