Do you not think when the 370 comes out you will see a lot of 350s traded in against them, resulting in more on the second hand market pushing down prices further? I've still not taken the plunge yet, that's what's stopping me.
I'm not conviced they will, reading what I do here and other places. The majority want a S/H 370z to let someone else take the biggest hit on depreciation. I think this will leave a lot of people keeping the 350z, at least for the first year of 370z sales. For me for example, my 350z is worth £10k if I'm lucky and although the 370z is a massive step up from a 53 car, its not worth me forking out £20k for. If the S/H prices of 370z are anything like the 350z though, I will be more than happy to trade in