Just saw the pixelated wiper + rain effect. Ugly indeed ! Skimmed through the official forum and GTPlanet forum to see what others say. It looks like people haven't focused on it yet (Still lamenting about standard vs premium cars, damage model, camera view).
Wonder if PD will do something to tone down the effect after launch. Kaz was concerned with dropped frame + rain effect for the delay. This must be one of the items on their hit list. It's too obvious to miss.
Also curious how many cars the game supports for a rainy track.
EDIT: I drove in a near-zero visibility rain storm before. You don't see the spray from other vehicles that clearly. The entire windscreen is like a water fall. Or rather it's like buckets of water poured over your windscreen. No matter how hard the wipers work, it looked like the car was under water. ^_^
So if they want to, they can tone down the spray, but work on the water effects on the screen.