I'm shopping for a new truck and what I've learned is that neither truck nor trailer salesmen know much about actual capacities. For example, the Ford web site says that the F-350 has a max conventional trailering capacity of 14,000 lbs - the keyword being "max". And good luck finding one that can actually do that. The best I've found so far is 12,500. Options reduce the trailering capacity. As near as I can tell, the GMC Denali package reduces the trailering capacity by 2,000 lbs. That's significant.
9000# This is your "wet" weight. It includes all tanks being filled like you're ready to leave home. It also includes miscellaneous cargo like dishes, food, lawn chairs, etc. It is the maximum that your trailer should EVER weigh. This is the important number.
7300# This is the "dry" weight. No fluids or battery. It may include the weight of your propane tanks but only when they are empty. Most of the time I ignore this number.
What is your actual weight? You need to take it to a scale to find that out. It will cost you a fee but this is extremely valuable information. Your wife wants to bring the ceramic dinnerware and her cast iron cookware? Oops, that just put you over the limit by 200 lbs. Get it weighed.
What is your tongue weight? The Titan is rated for only so much tongue weight. A tongue scale is a good investment. Or, when you're at the commercial scale see if they'll let you get the tongue weight.
The Titan cargo weight also come into play. The formula is this: Max cargo weight - actual tongue weight = amount you can actual load into the Titan (including people and gear). Hopefully your wife won't need to go on a diet for you to take her with you.

You should never exceed the GVWR of the Titan. The GVWR should be listed on the white tag at the bottom right of the driver's door frame. GVWR <= curb weight of Titan + cargo weight + tongue weight.
The user manual has a chart that explains what the max trailer weight and max tongue weight can be for your Titan. But you need to know your model and packages. Here is a thread that shows an example for 2007:
Towing Capacities Chart - Nissan Titan Forum.
In shopping for my new truck and trailer my goal is to not exceed 80% of the tow vehicle's capacity. I will be driving over many mountain passes here in Colorado and Wyoming. I don't want to kill my truck because I have a trailer that is too heavy. If I was always towing on the flats, I wouldn't have a problem bumping up the limit to at least 90%.