I've noticed a few pictures here with what I think are '10 model 150's with 6 lug wheels.

Unless I'm mistaken, mine only has 5 lugs. I've not taken the centercap off, but it sure looks like a 5 lug cover.

Thankfully, I got the 17" wheels, is that the difference?

 

No, all F150s after 2004 had 6 lugs unless you got the Heavy Duty Payload package which makes them 7 lugs.

Your 2010 has 6 lugs on it.

 

Huh, cool.

I just noticed the center cap and wondered. I guess I should have pulled it off to see what was underneath :o