I was on christmas eve flight one time, and on one of the very few AF flights on millenium (yes! I mean less than a half dozen flights was maintened, only B742 and 743, wich means no much electronic onboard, so no chance of bug!!! arrival at 6.00 am at orly airport was very very quiet!!!)
Both flights was in Y, and I don't remember captain dressed in father christmas came in the cabin giving free vouchers for flights to all passengers... Maybe in C????
I just remember of a little bottle of champagne for the dinner (no champagne on CIO flights in Y, after all, in french overseas department, whe don't need AF to drink champagne!!!)

For the millenium flight, I have heard that the upperdeck cabin (B742) was closed and reserved for PNC party.... but I can't confirm... We were served duck instead of chicken this time (yes! two times duck, and maybe between 50 and 60 times chicken...., or "volaille", wich means turkey... (no choice of meals on....)

Have a good flight