[CentOS] bind: root hints named.ca and named.root

For 6.x I have both of these files in my /var/named directory, probably copied when upgraded.  named.ca date inside the file is dated 2008 and named.root is from a few months ago.

Am I correct in assuming that named.ca is old and that I should be using named.root in my named.conf files?  Is it SOP to use the latest from ftp://ftp.internic.net/domain/named.root 

thx

-- Mike