Either way, unless you are looking to buy a car NOW, I'd wait a year.
If nothing else, the coming of the Z35 will make it easier to buy a Z34, which a dealer will be itching to get off the lot once the next model is confirmed and ready to ship.
On the other hand, if the Z35 is that much better, you may also kick yourself for not just getting it when it becomes available.
My 2011 will be paid off just in time for the 2nd MY of the Z35 -- that will give Nissan a chance to work out some of whatever new model bugs crop up
