I thought each release of Centos had a longer support life cycye than this.
It does. You're confusing major/minor versions. Centos4 will be around for ages, centos 4.1 is centos 4, plus the quarterly security updates etc, all rolled up in a new iso, so that you don't have to immediately download 200 updates after installing 4.0.
4.2 is 4.1, plus the next quarterly update.. and so on. It's not a new version, it's a rollup of the major version, plus updates. Same with version 3.
hughesjr had a link on centos.org at one time explaining the naming convention and it's relation to upstream vendor versions. I seem to have lost the link, but perhaps it's time to trot that out again. If someone following this thread has the link to version/naming convention, please post again to help clarify this.
What then is the difference (in this respect) then between Centos and Fedora Core?
Fedora core releases a new major version 2-3 times a year. centos releases a minor version update (essentially security errata rollup. think "windows servicepack" for lack of a better analogy) every few months.
-- Jim Perrin System Administrator - UIT Ft Gordon & US Army Signal Center