[Centos] Update ?

Wed Nov 3 05:01:27 UTC 2004
JD. Brown <brownstixzz at yahoo.com>

I realize that up2date and yum are two different methods of updating with CentOS.
My question is this? I updated my yum signature key. Downloaded all required updates and now
up2date still complains of 500 more updates after the initial count was 514. 
Should I worry about this or what hack is known to fix this? 
I looked around the web and only found people talking about "Yum" and only one site making
referenecs of fixing up2date with no follow ups.
I'm just concerned about this? Other than that, I'm very happy with CentOS.

Thank You,
JD. Brown