Being the middle of summer here (often up to 40'C plus), we like many others, have opted for a mainly cold lunch. Seafood Christmas lunch has become very normal in Oz, although a lot still do trad turkey etc.
Our lunch now usually / always includes:
Smoked Leg Ham sliced from the bone, (many households buy a 10 kg whole leg at this time of year)
several kg of class A prawns. Schoolies, Crystal Bays, Tigers or Kings (or all 4)
cold roast or rotisserie bbq chicken and pork.
fresh Sydney Rock Oysters w/ sea salt, pepper and LJ. (sometimes some cooked ones as well Kilpat' &/or Opera)
Blue Swimmer Crab (usually caught by me so I'd better get out there in the next 48 hrs)
Several different salads
and the only hot cooked fare is beer-battered fish cocktails and potato chippies but these are a given.
A variety of Seafood Sauces and condiments.
Nuts, candies and cheeses
Deserts are more traditional with Xmas pudding, custard, trifle, ice cream. etc.
This follows from breakfast, which is usually fried leg ham and eggs, but needless to say that since lunch usually sits for 3 - 4 hours we don't eat much dinner.
We used to have more traditional roast foods on occasions depending on whose family we ended up with for the day, but the kitchen is not a place to be on hot Christmas days.
So No to curries for Christmas.