The LAN (Chile, Peru, Argentina, Ecuador, Colomiia) airline empires does not.
LY- from my experience DOES not.
NH- DOES not
AA- I'm confused about this one, I have had a couple of ZED flights on AA were I was not upgraded. However, I flew from ORD to MCI a year and a half ago and was upgraded (go figure). I believe official policy is no upgrades.
AC - DOES not.

I have never nonreved on NK but I am assuming by upgrade Tony means they move you up to the so called BIG LEATHER SEATS? (Their version of C class).

Regards,

Chepos