It says late 2010 which is a 2011 model. 2009 was originally when the Z was going to get the 3.7L in the current body but that is now delayed.

 

Why? What's wrong with the VQ35HR ? It lacks some upper end HP.. but it has the same torque.. It's about the same performance... Infiniti had to try and make the G37 more attractive... so they came up with some more HP numbers.. as HP sells cars.. The difference in performance is minimal at best.. you would be lucky to see a tenth of a second difference in performance..

 

it's also the variable timing thing, gives higher end HP and better efficiency (fuel improvement as a bonus)...

yeah, for the most part, people probably can't tell the difference in terms of performance... and how many people are going to track the g anyways...