As long as you buy Nissan paint, the code is what you want to go by. According to this Nissan parts site, it's Storm Gray. That also matches up with marketing materials from 2006.
http://www.courtesyparts.com/1/2-touch- ... =5906_5906
Sometimes they will sell the same color with a different paint name depending on the model/year. Mine is A15 Red Brawn on the Pathfinder but it's called Sonoma Sunset on the cars.
Aftermarket paint sometimes will use totally different names and just cross-reference codes. I've never had good luck with after-market touch-up paint. OEM stuff is hard enough to match.