The magic date used to be 1st January, but book keepers changed this about 10 years ago to 31. December.

For all of 2012, you pay your taxes (Not tax taken at source) where you are registered on 31. December.

Be careful, the government offices are often "half closed" after Christmas.

Rental properties are difficult to find for the end of December, as many rental contracts do not allow a move on 31. December.

So if you are renting, look at 30 November as a possible moving date. And as many contracts have a 3 month resignation clause, you should be looking for properties right now!