Several key points for U.S. legacy carriers:

1) The economics of FF miles have significantly changed for the airlines based in the U.S due to the price of oil. The airlines can not continue to add mileage liabilities via FF credit cards in particular without adjusting their reward structure. Whether fees are tacked on as fuel surcharges or called something else, they are necessary (the other option would be to change the mileage requirements but there appears to be more hesitation in going that route on a wholesale basis).

2) The risk of holding massive FF miles in a single legacy airline has gone significantly higher, because a bankruptcy this time around could mean shutdown. But it is very unclear which carrier may be the first to fail.

3) Some airlines seem to continue to provide good value on awards, DL and AA are mentioned frequently, and I have had good luck with UA (US is ok IF you can get a *A award).

4) A FF mile that I plan on redeeming immediately I would value at 2-3 cents minimum on AA, UA, etc.; but a mile I wasn't planning on redeeming for 18 months I would probably value at less than 1 cent due to uncertainty.

5) With less flights and more people trying to burn miles, awards and upgrades will likely be more challenging to obtain. However, is it possible that loads have fallen so much that more awards are currently available for certain routes just to fill seats and remove the liability?

6) You can't ignore the impact WN is having on the legacy carriers in your thinking about the future.

I am not status anywhere, but still have about 100k on both US and UA that I will be burning down when possible over the next 18 months, after just being able to get 2 IAD-Hawaii *A awards on UA metal using US miles. I probably will eliminate my airline credit cards in the next year as well.

My 2 cents FWIW.