We bought our 2010 Limited (4WD) in November of 2012. It's the model with the slide out tray instead of 3rd row seats. Since we bought it, we've put about 11,000 miles on it.
After test driving the 4Runner, Pilot, Pathfinder, and several others, we felt that the 4Runner would do best to haul our family on many adventures. Right now, our family is myself, my wife, and our two "fur-kids" (two greyhounds, 55 pounds and 75 pounds). We think it'll still work great when we add a "skin-kid" to the mix.
Like I mentioned, we've put about 11k miles on it since we bought it. That included a 3,000 mile holiday journey from Texas to Minnesota and Wisconsin. During that trip, it performed AMAZINGLY! The trip was smooth and quiet. (Coming from 1998 Jeep Cherokee, I was blown away at how quiet it was inside the cabin. Even now, months later, I still feel it is a quiet cabin.) Over the course of that trip, I think we averaged between 19 and 22 mpg at most of our gas station stops. I know we had the wind at our back as we cruised through Iowa, and we hit 24.5 mpg.
Other than big trips, I use the 4R as my daily commuter. I drive 15 miles to work (30-35 minutes) with some stoplight roads and some highway. I've been packing 150 miles on every week since we bought it. In those driving conditions, I've still been getting 19.5 mpg pretty routinely.
I hope all this helps. Feel free to reply or send a PM if you want more info or if you have specific questions.
-Joel