Gatwick 去 Victoria...

A special coach service with journey of approximately one hour will operate
25 December 2007 to 25 December 2007
There are no train running on x'mas day.
A special coach service with journey of approximately one hour will operate between London Victoria and Gatwick Airport departing from London Victoria every half hour between 06:30 to 16:00 inclusive with a final service at 16:45. Departing Gatwick Airport between 06:30 to 16:00 inclusive with a final service at 16:45. You can go to their web site to book ticket (Advice)or buy the tickets on the station.

The underground time table is not come out yet. Should be checked the underground time table on the early on December. They should have some special arrangement.

I hope it can help you.

2007-11-28 04:28:34 補充：
New information on x'mas day's transport from Victoria station, london, to Heathrow. National Express would launch new service called dot 2 dot pick up from london city to Heathrow. Check the web page of national express.