All music, songs, and worship in God's assembly ought to point us directly to Jesus. Especially around Christmas time, be careful to remember that carols and hymns ought to reflect what God has done for us. Ultimately, Christmas and worship are ultimately linked.
Do we worship God for the right reasons? We don't worship Jesus just because He's king; we don't worship Him because of what He can do for us. Actually, we worship Him so that He would be King over every area of our lives.