There is no such a thing called Christmas#1 in US. that term is actually for UK only. Every year artists compete for that prestigious title, which is nothing in US when it comes to prestige.
But it still means a lot in the US for name's sake and sales. Ke$ha got 619k Christmas week last year.
In the UK they do that on the big radio stations. they just stick to the playlist constantly. (excpt xmas songs). I heard LTWYL Part 2 and Raining men on Uk radio. i cudnt believe it.
They play the same songs over and over. 
