One of the aforementioned sources (checkiday.com) has this to say re today's holiday:
"Santa's List Day is the day each year when Santa makes his list of children that have been naughty or nice, so he knows what to bring them for Christmas. Santa learns who has been naughty or nice after hearing from his elves. The Elf on the Shelf, a children's book published in 2005, talks about elves that visit people's houses from just after Thanksgiving, until Christmas Eve, and report back to Santa each night about who has been naughty or nice. It seems odd that Santa's List Day is celebrated so early if his elves are still keeping a watchful eye on children... It has always been observed annually on December 4th."
Because checkiday mentions The Elf on The Shelf, I'm giving this fictional story-book character a nod by including photos of a Macy's Ballon which is rendered in his likeness. The images were taken by yours truly a couple of years ago at the annual Macy's Thanksgiving Day Parade.
At the parade, I observed that The Elf on The shelf seemed to have something in common with the wild bird known as a male Northern cardinal. They both appear to be voyeurs!