There were a lot of cool innovations from PT Shadows Over Innistrad. We finally saw the emergence of powerful Elder Deep-Fiend strategies, and Emrakul, the Promised End made her presence known. Both Andrew Brown and Owen Turtenwald cracked the Top 8 of the PT with similar strategies, though quite different takes. Some self-mill, Kozilek's Return and big fatties are consistent between the build, though there are significant differences in the rest of the deck:
Owen's build is heavily focused on the graveyard elements with a strong delirium focus, and Brown's list is more invested in emerging Deep-Fiends quickly. Owen plays very few creatures to sacrifice to emerge, and one of them is even a one drop! As Owen demonstrated in the event, just casing Deep-Fiend for eight can still be a game-winning proposition, and at a glance I'm more partial to Owen's list.
Realistically though, I can't see myself playing a carbon copy of either deck. Frankly, both are still a bit rough around the edges, and I'm excited to see how the archetype evolves going forward. I would definitely like to maintain the elements of Owen's deck that allow him to operate so light on lands, and I would also like to figure out which creatures that Brown features could be upgrades to Owen's list. I know for sure that I don't want to be casting Primal Druid, as I have been disappointed by Viridian Emissary more than enough times. I am really curious about Owen's omission of Traverse the Ulvenwald given the consistency that the card provides, and I wouldn't be surprised to see some number of copies of that card featured in similar lists going forward.
However these decks evolve, what we know for certain is that they will have a significant impact on the Standard metagame. The ability to find and trigger Kozilek's Return so consistently is going to change the way that we build decks and sculpt game plans. I've been calling Kozilek's Return a good pickup for some time, and this weekend the card doubled in price from $5 to $10. I don't expect the card to game too much more value unless these decks evolve into the most played deck in Standard, though the Kozilek's Return decks aren't going anywhere, and no Standard gauntlet will be complete without them.