"I can never be what I ought to be until you are what you ought to be. You can never be what you ought to be until I am what I ought to be. This is the interrelated structure of reality." -Martin Luther King, Jr.
He is very practical and concrete, but his humour is also very Ne... like watching his improv stuff.
"McLovin'? Sounds like an irish R&B singer?"
"McLovin? Sounds like a sexy hamburger?"
and if you watch the extras of superbad, a lot of his scenes are mostly improvised, and you see how Ne is used on the fly.
I think the point about his concrete, average joe sensibility is very valid, and his humour is different from Louis Black, Dave Chapelle, and even George Carlin, but he still seems to use Ne, which is why I'm still thinking he has Ne.
Micheal Cera seems NF. At least he plays NF characters all the time.