I'm sure this has been mentioned at least somewhere in this thread but when I bought my 08 4Runner Sport V6 new I liked the fact that I could operate it in 2WD mode, whereas you didn't have that option on the V8 model. My own 4Runner has probably spent less than 5% of it's total 170k miles in 4WD as I primarily drive on the freeway, but of course use 4WD for winter driving when it is warranted.
Just seeing the difference of 1-3 mpg when I operate mine in 4WD mode was enough for me to justify the difference. I'd likely appreciate the torque of the V8 engine for sure, but overall my V6 has been a wonderful engine for 170k miles and counting.