We are two multi-year Delta elites (plat last two years) who comped to NW last January. So far, it's working out really well.

If Delta hadn't screwed with the platinum upgrade system, we would have stuck with them, paying higher fares and taking less convenient flights.

Dumb us. We upgrade as often on NW (although with a shorter window), pay less, can consistently fly reasonably from our home airport, and have better flight time choices. Plus there's decent food in first. Plus when we cash in miles for a coach ticket, we can upgrade. Plus the new Detroit is awesome and WorldClubs are great. Well, I could go on and on. We each expect to earn NW platinum on miles flown this year.

But it's all because they dinked our old SkyMiles program. Oh, the unintended consequences!