Thanksgiving Challenge
Main difference between this and Halloween is that it's literally no longer a "competition" against other players.
i.e. No more leaderboard rankings. The challenge now is simply to shoot down as many flying turkey pigs as you can.
There appear to be five milestone levels, each of which awards an unspecified prize (it's inside a hidden gift box).
The first level is to pop ten pigs. The prize is coins (didn't track how many but I think it's 5,000 - also, don't know if that's random, or if everyone gets the same prize).
The second level is to pop an additional ninety pigs (i.e. 100 including the first level). No idea yet what the prize for that is.
The challenge commenced at 3am EST (8am UTC) and ends six days (144 hours) from then.