Hmmm...I had quite different experience yesterday.

Outbound 8:55 EWR-CVG (Express), the eService kiosks were fairly busy, but there were exactly 3 people in line at the main check-in desks at 7:30 AM. The gate area was somewhat crowded, but my ERJ-145 had a load of about 40-50%. Seatmap on the eService screen showed a much more full flight - apparently quite some no-shows.

Return (19:40) CVG-EWR (also Express) was even more empty - despite the 17:25 flight having been cancelled, we only had 12 of 50 seats filled - two of those by employees.

On the outbound, I observed the gate-checked baggage, and nearly every piece had an Elite tag - apparently, either all CO flyers are Elites, or its only the heavy travelers that have returned.

As a semi-related aside, w/end trip JFK-ZRH-EWR on SR - outbound (Thursday) was 50% in economy, 10% in business (didn't see First). Sunday return had 90% load, but only because JFK departure at about the same time had been cancelled. You could hear echoes in the Terminal B immigration hall.