"O Holy Night" - Who Sings The Best Version?

Which is the best version?

Nat King Cole:

http://www.youtube.com/watch?v=gSeLzsl8xsU

Johnny Mathis:

http://www.youtube.com/watch?v=0yHHbJt85-M

Josh Groban (at least the best video):

http://www.youtube.com/watch?v=4Zh-yR0pbmU

Andy Williams:

http://www.youtube.com/watch?v=W-RAnkH8Jxc