The one thing I noticed is that a few of the companies are using a b+ rear wheel and a 29" front wheel which is my preferred setup on my mtb and has been for awhile.
I like the grip and give of the fat rear tire and a narrower tire on a wideish rim up front at a similar low psi provides very precise steering. Too big a front tire at a low psi has to much contact area and tends to grab and self steer too much for my talents. I don't go all that fast downhill any more but that 180mm travel Fantic makes me want to.