So What do I think?
Some of the new Mechanics are pretty kewl and another twist to the well balanced game that is Warmachine. The focus mechanic presented in the video was kinda kewl and the RAT/MAT mirroring is odd but unique.
Nothing feels broken from the video.
While a new Hordes faction would have been hard to explain outside of creatures from beyond the seas as all of the current continents factions of beast manipulating factions have been given. Picking a Warmachine faction feels odd as the Retribution faction that was released with Mark 2 (the current rule set) is just catching up with the other factions.
Is Privateer Press going to bring out this smaller faction, and raise it up like it the Retribution over time?
I'm not sure but I feel that they've looked at how it fits into the game and it will be it's own thing.
Warmachine and Hordes is my favorite table top game simply because of the balance and way the company treats its customers through their products.