Reading this thread, and especially MikeMpls made me smile and sad at the same time.
Mike is in almost the same place I was when WN came to Denver 3 years ago. You discover that there is an airline out there that can treat you nice, even if you don't have status with them. I switched from UA to WN, just like Mike did from NW to WN.
It also makes me a bit sad, though, because I remember all the upgrades I got, with no hassle, as a CO SILVER flying NW metal from DEN-DTW-DEN back in 1999-2001. Only one time did I miss my upgrade and another time, I didn't get it until about 8 minutes before departure. Other than that, it was pretty sweet.
My handle FC (for) free, reflects how much I enjoyed my NW upgrades. It is sad to hear that they are so much harder to get, between the DL merger, the use of the Jungle Jets and probably just a greater number of SILVERS and GOLDS competing for them.
The next best thing to a free NW upgrade is an open middle seat on WN.