One problem related to software has been reported for the 2009 Infiniti G37. The most recently reported issues are listed below.
On a cold snowy evening while driving on the highway at about 60mph the car began to violently shake, when I took my foot off the gas pedal the car stopped shaking, when I tried to accelerate the car again began to shake violently. Fortunately I was about 5 miles away from my destination and managed to drive about 25 on a highway. After I reached my destination I powered off the car and let it sit for about 5 minutes, then I powered it on again and tried to accelerate above 30mph which caused the car to shake again. I ended up getting the car towed to the dealership, when I got a call back from the dealership the next day, the mechanic said that the problem was due to a software issue with the car. During the cold weather the air intake was not taking in air correctly which was causing the engine to misfire. I was a bit skeptical about what happened but since then I have not had the issue occur again. Infiniti should make this information known to owners either through a recall or update the software during routine maintenance.