By the way, the new 2009 Alaska Upgrade details are posted on nwa.com. I just found these:

http://www.nwa.com/offers/alaskaupgrade09/

Basically it goes like this:
Y and YAS fares - call Alaska Airlines directly and ask them to upgrade you right away. There still has to be "U" class available for the upgrade to go through.

Coach fares - only available day of departure when you check-in; you request to be put on the standby list for an upgrade.

Two things about the coach upgrades: 1) there's no mention on nwa.com where NW plats/golds fall on the list. I still believe it's at the bottom based on my recent experiences. 2) AS was supposed to be implementing an automated upgrade procedure for NW & DL elites starting March 1. I don't think that's in place yet but maybe AS is still working on it. Maybe then AS will make NW/DL plats equal to MVP Golds and NW/DL golds equal to MVP or something.

I'm off to call Alaska Airlines to request the upgrade for my Y fare flight coming up.

-RM