Been waiting to post in here until I got at least 1 mod on the car. Got the Z in Feb. I had an 05 STi that had quite a bit of mods done to it. The Z is quite a different car in a lot of ways. So far I am happy with my choice though. For the last couple of years I have been doing HPDE's about 4 times a year when it is cool enough outside. I plan to continue this with the 370Z. Here are pics and mods.
Mods:
-BC BR series coilovers (10k/8k F/R spring rates)
-Rear camber arms
-Alignment: 0 toe all around, -1.4F -1.7R camber
-Berk HFC's
-Fast Intentions catback exhaust
-Carbotech XP-10 F/R brake pads (track only)
-Motul RBF600 brake fluid
-Stillen "Race" oil cooler