The first obvious part is the rear end. Most bumbers nowdays are "designed" or integrated into the rest of the car. The NSX bumper is much like a shelf. An S2000's is also like a shelf, but with a curve to it. The perfect example is the TT or G35 coupe for bumpers. Another example is the taillight. It has the simplicity of an 80's stereo system or what we automotive designers call "Robocop design"
The lenses used are also another giveaway. Most lenses used nowdays are clear red without the "filter" element. Rx-8, Audi Lemans, Infinity FX and G35 are good examples again.
Another thing is the design "language". The NSX resembles the earlier preludes in terms of design language...just a much more superior one ofcourse. Its very mechanical and angular, but different than today's angular designs (Cadillac, Gallardo, HSC, Z4) The new cars use what we call "Faceted" design..similar to jewels or like the stealth fighters (BMW has their own "Flame Design")
Overhang is the one you already mentioned. Another clue are the creases. Technology has come such a long ways when it comes to stamping material. The tolerances are higher now, enabling sharper creases in sheet metal.
Another clue are trim pieces...ie the silver strip on the doors by the base of the window. Weather seals also look different now. another trend followed nowdays (in terms of porportion) is what we call "beltline". The beltline is raised higher (S2000, 350z, Vanquish, TT, A4) making the green house (cabin) seem smaller. That's why the newer cars have that "slab sided" look. The driver seems like he's sitting lower in the car with the top of the door all the way up to his ears. Cars are starting to look more and more like our sketches and design concepts.
I remember the TT being a major breakthrough for car designers...finally the designers get recognition rather than just designers. The TT didn't do anything special other than prove that a designer in control and make a successful car.
Ok, the most obvious are the pop headlights and interior, but thats why we have the '02 facelift...unfortunetly for the trained eye (even though its quite a looker
) it wasn't enough to disguise the overall age of the car.
I post more when I can remember. I hope that helped. :redface:
Ps. The same goes for movies...Star Wars...the techniques, quality, sound, lighting, editing, designs etc. are old, but are they bad? Nope. In fact I think Ralph Mcquary is a better designer than Doug Chiang.