I've had my current V6 08 for about 5yrs. I thought the spark plugs were changed before I got it around 110K. Looking at the carfax, it was actually done at 59K, has 170K today. There were NGK Iridiums in there, and I just replaced them with the same.

Passenger side were hard to get out, like there was anti-seize on the threads or something. Driver side all came out really easy, and felt undertorqued compared to the passenger side. The middle driver side had orange like burnt marks on the ceramic, and looked like it could have been wet. The rear one was definitely wet, and when i looked in the engine chamber, there was a little bit of moisture by the threads area.

All of the spark plugs were worn down to a .75 to .85 gap.

I did have an oil analysis done very recently, and the oil looked good, although they found a trace amount of fuel in it. I had the same trace reading at 135K, but not 160K.

Any idea what could be going on here, and how much trouble I'm in?

It's not a big issue, that just oil that leaked past the valve cover spark plug hole seal, that oil can't really go anywhere other than around the spark plug.

To solve the issue if you choose too is to replace the valve cover gaskets as well as the valve cover spark plug hole seals, just checking to see if the bolts for the valve covers are torqued properly may stop the leak/s if they're loose.

If you're worried about something like a failing head gasket, you can test the coolant for exhaust gasses. Otherwise I'd change the plugs and monitor things like coolant levels and such.

Like Mike said above, just put in new plugs & keep a close watch on coolant levels. If you are really worried, get a cheap borescope to hook to your phone & see if there is any coolant in the combustion chambers.