When is the Strictly Come Dancing final 2009 on?

The final is pretty much always the Saturday before Christmas so I'm guessing it will be 19th December. If there are 10 couples dancing this coming Saturday (31st Oct) then by the 19th Dec there will be 3 couples in the final.
I'm having my annual strictly party then! Get al your friends round and laugh at the costumes, enjoy the music and the pretty dancing! And get food too!