Well I did a bit of a tune-up today and changing the spark plugs was on the list. It's on a 2007 Tacoma V6 4x4.
Here's a couple of the plugs I pulled out. All plugs looked like the first two pictures, but the driver's side plug closest to the rear of the truck (don't know the # of the cylinder) was a little wet. It was the only one that was wet though.
Plugs likely hadn't been changed EVER. They were the typical Denso on one side and NGK on the other which I've only ever seen done by the factory, and the truck has about 80k miles on it. My guess is those plugs have 80k miles on them as well.
Also it's "interesting" to note that all of the old plugs were eroded away so much that the gap was over .060 on all of them. One was as much as .075 !
No wonder my mileage was so bad!
And the wet one