>It's always the 4th Thursday in November.
And the day after is the Black Friday (i.e. start of the sales season, when the merchants' accounts go from red to green) aka Food Memorial Day (when America eats yesterday's leftovers).
> It used to be that you saw Halloween or Harvest type decorations in October, Thanksgiving decorations in November, and the week following Thanksgiving the Christmas decorations went up.
They stuffed Halloween merchandise into isles as soon as they sold more than half of the Back To School stuff - last week of August. And the Valentine stuff competes with Christmas leftovers for about ten days, up to 7th of January or so.