Yes, this is correct. I was responding to a post which basically had the point "life is obviously good for plats, but what about golds and silvers," so I was speaking from that perspective.

I wanted to add a couple of other thoughts about the question of DL vs. NW for folks reading this thread. I got the temporary silver membership when my company's travel agent priced a RTW ticket for a biz trip on both DL and NW. DL ended up pricing out less on the trip so the company ended up picking that. Consequently, I basically ignored the comp Silver because I figured I wouldn't get enough miles on NW, and made my 25K on DL primarily from that RTW ticket.

Later, I learned of the partnership between NW and CO. I had a biz trip on CO in mid June and a leisure trip to Europe on CO in late June. Due to school and work commitments, I had only 4 available weekends in late May and early June to fit in the three M class or higher trips the challenge required to keep silver for the year. I elected to do it. Because I fly out of a non-CO/non-NW hub, I ended up with a 100% upgrade percentage on all flights for which elite upgrades were available. After the two international CO trips mentioned, I ended up with about 19K miles on NW. I focused the rest of my leisure travel with flights on NW (along with 2K miles thanks to Hilton as a partner in that 200% partner match) and made the 25K goal by the end of October.

Ok, so that's my history here on how I got silver on both airlines. In the experience of getting both, I honestly believe NW works better for me in terms of both what I get as silver (unlimited, space available upgrades compared to the 4 800 mile segment upgrades) AND the ability to USE those benefits. If you are in say DTW, MEM or MSP, your experience would very likely be the exact opposite of mine, because you'd have more competition as a silver for getting the upgrades from NW just as I do getting upgrades from DL. YMMV.

As for customer service (the other question raised in this thread), I've honestly never had bad experience from either, not even as a basic member. I've had things that didn't post right on both, but those things have always been corrected within a timeframe that satisfied me. And I've never been treated rudely in my travels by either NW or DL ground staff or flight crew. I suppose I've just been lucky or maybe I have lower expectations than some folks.

But to sum up, being based out of a DL hub, I can't benefit much from any elite tier lower than plat while I can benefit even as a silver on NW. In my mind, NW gave me a good opportunity to earn silver easily the first time and that marketing tactic paid off for them because I changed my flight habits to keep it. That's what elite challenges and comps are all about, for any airline. I suspect that if the thread originator does NOT change his flying habits next year, DL is no more likely to grant him an extra year of elite status based on what business he MIGHT bring to them than NW demonstrated.