This year has been a bumper year for Silver and Gold upgrades. I would guess that fully 30% or more of my flights go out with empty FC seats. That means it is upgrade time for those who usually sit in the back. I have met a guy who last year never got an upgrade as Silver on the TPA>DTW run. This year he is 5 for 5.
We all know that won't last, but it will last until the economy improves and business travel resumes anything near normal levels.