Smell that, Legacy? Smells like bullshit!
If anything, Infinity Ward is doing anything but making a game like Battlefield. Tanks and jets usable in the game? I would definitely cancel my pre-order if that were to happen. I think what you mean is that for certain maps, (let's use Free Fall) you will land in via helicopter or parachute when the game starts (the countdown). And for other maps (flat, large maps) maybe you will ride a tank in the map.
And for killsteaks, the whole "hidden killstreak" for certain types of strike packages would be a good idea. For instance, maybe they would bring back some sort of nuke for Assault packages. Then in another, like Support, maybe some sort of indestructible support aircraft you can call in. Idk. Just an opinion.
But personally, I think they're just going to make it so you can enter the map in a different way, just to spice things up. They wouldn't make the game ANYTHING like Battlefield, otherwise gamers would just buy Battlefield.