Apparently Infiniti / Nissan considers the fluid in the 7-speed transmission to be "lifetime" so doesn't have a recommended interval for it.

I recently picked up a 2012 G37 w 82k, really like it a lot, but not doing so much as a drain/fill on the transmission seems hokey to me. Any opinions on the matter?

I think they should determine how long the "lifetime" is.

There is no lubricant currently that lasts forever. Likewise there is no transmission that doesn't produce spooge in the form of clutch material and metal chips.

Take what you will from that.

Dispose cars. Designed to fail, or to be vulnerable to failure within a certain lifespan. Probably whatever will outlast the typical extended warranty a sufficiently high percentage of the time. Many CVT are factory sealed and not really serviceable, just replaceable.

Drain and refill it.

Both year and mileage play a factor here. I treat it like a timing belt which calls for 90-105k miles or 6-8 years.

I'd do 100k. If you drive aggressively then sooner.

The real "lifetime" of a vehicle is the warranty period. That is the period where failure of any component is extremely rare even for hard driving.

Many owners manuals have a section that specifies the service and associates mileage. I'd consider "lifetime" to be whatever mileage those service logs end.

Thanks all. The maintenance schedule goes out to 150k. I don't know how it was driven for the first 81k so I'll probably pay to have a drain and fill (no dipstick, and the need to have the car lifted and level makes me wary of doing this myself). I'm going to do it now.