If anyone's interested, I just took a peek at the new vehicles with Open IV.
Coming soon to your single player game near you once RPH and/or SHV + your favorite trainer have been updated:
Alpha 1Z: WW2-style fighter, likely based on the Supermarine Spitfire
Bombushka: Medium-size 50s-60s soviet cargo plane (or bomber), loosely based on the Antonov AN-12
Coil Cyclone: Sports car, not sure based on what exactly - maybe a Zenvo ST1
Havok: Single-seat helicopter, likely based on the Mosquito XE
Howard: WW2-style single-seater, although its features seem a little exaggerated, suggesting it may be a stunt plane. Not sure what's the real-life equivalent.
Hunter: This one needs no introduction. AH-64 Apache helicopter, but with the tail of a RAH-66 Comanche... pretty cool concept.
Microlight: The ultralight aircraft seen prominently in the trailers.
Mogul: WW2-style small bomber with a bubble turret. Loosely based on the Lockheed Hudson.
Molotok: Cold war era soviet fighter, based on the Mig-15
Nokota: WW2-style fighter, clearly based on the P-51 Mustang - not sure why they didn't call it the Rustler.
Pyro: Twin-seater jet with a double tail - not sure what it's based on, but it looks like one of those late-WW2 german designs that never saw the light of day.
Dewbauchee Rapid GT (3 or "classic"): 70s sports car, based on the 1970s-1980s Aston Martin V8 Vantage
Vapid Retinue: 70s compact rally car, based on a 1970s Ford Escort Mk1
Rogue : Twin-seater, single prop military trainer aircraft, loosely based on the Diamond DART 450 - it appears to have a Zancudo livery.
Seabreeze: Twin-seater plane with a tail-mounted prop. Looks exotic, I'm not sure if it's based on something real.
Starling: Late WW2 german concept plane, based on the Messerschmitt Comet
Tula: That weird short WW2-style cargo plane with 4 props and supposedly VTOL capabilities seen in the trailers...
Vigilante: Heavily based on the 1989 Batmobile, but with the Tumbler Batmobile's rear end. No, I'm not kidding. And yes, it has a friggin jet turbine.
Grotti Visione: Exotic supercar based on the Ferrari Xezri concept.