Just had to say… 
Next time, please refrain…
Best night to watch the map for what? Extra UPS/FedEx flights? Passenger flights? General aviation flights?
The airlines may have added some flights but I don’t think they added very many. The goal of the airlines now is to have fewer aircraft flying. This means less seats, higher load factor, and (hopefully) profitable flights.
AFAIK, while during the holiday months there is some increased service overall, there isn’t one particular day that is overwhelmingly busier flight schedule wise. Usually airlines will simply add a few extra daily flights from early November into early January, and perhaps very sparingly they might bump up the aircraft sizes on a certain day as demand dictates.
Generally speaking, though, you aren’t going to see much of a visual difference on the maps. Busy hubs like Atlanta, JFK, and O’Hare will look as busy as they always do, and less busy regional airports will look typically low on traffic, besides maybe seeing a few more mainline aircraft flying in.
However, you may see (albeit slightly) increased activity at the freight hubs (ONT, MEM, SDF, PANC) and their smaller bases. With a lot of people buying online more this year than before, freight carriers will definitely be busy.
BL.