While SE shouldn't release the patch on Thanksgiving, that's not to say they won't. Anyone who played FFXI through Wings of the Goddess should remember the huge debacle when the publishers SE hired were authorized to ship on the day before/on the day of Thanksgiving, which ended up delaying a huge percentage of the NA players' discs until the following Monday. That's a much bigger deal than the upcoming patch, they didn't consider the US holiday then, and I doubt they will now.
As someone else stated, they have been staying slightly ahead of their announced times for many things, and there's a good chance it'll continue for awhile...if for no other reason than they want to stop the bleeding.
Jerri Blank (Strangers with Candy):
"I may still be doing all the wrong things, but now i'm doing them the right way!"