A few other things of note.
Skyfire lets you shoot at flyers, flying monstrous creatures and skimmers at your normal ballistic skill. Snap shots against everything else even if you have interceptor. Which kind of sucks since I liked giving my Orks the 96" range Icarus Las Cannon.
Sniper Has been nerfed a little bit. It no longer rends against vehicles. Instead they are resolved at strength 4.
Rend Is still AP 2 against models but not against vehicles. The extra D3 armour pen is resolved at the weapons normal AP value. So no more blowing up Ironclads and Mega Dreads with Pask in a Leman Russ Punisher.
Skimmers are no longer automatically wrecked if they go flat out and get immobilized. It looks like they can still Jink even if they're immobilized though. And as far as I can tell jinking doesn't cause the passengers to also snap fire. The book also clarifies that vehicles can take cover saves against any weapon that would damage it including grav weapons.