We're the vehicle chapter, so the new vehicle rules are obviously going to be a boon to us. Some of the units that will benefit from these are obvious -- Land Raider Redeemers and Crusaders have been a topic of some discussion so far -- but in particular I want to highlight the Ironclad Dreadnought.
It's T8 and sub-10 wounds so it can be hidden from shooting with the character Dreadnought strat, and as a melee threat it really benefits from the +1 attack from that strat as well. But specifically, it now is going to be extra murderous against infantry. Whether you go double-melee arm with double heavy flamers, or one heavy flamer and a hurricane bolter, the ability to not only punch enemies you're engaged with but also to shoot them while engaged? Oh boy. I foresee a lot of pain.
Another thought I had was regarding Predators. Traditionally, I like them as an anti-tank platform with all the lascannons, but would make them extra easy to tie up in 8th Edition. Moving into 9th with what we know at the moment, I feel like heavy bolter sponsons are actually the "meta" choice regardless of what weapon you take in the turret. It gives the Predator a degree of flexibility and a decent ability to land hits not only on Overwatch -- especially our Overwatch -- but also when shooting while engaged.
So those are the first thoughts filtering through my mind. What vehicle are you looking forward to running in 9th right now, and why?