SL is an exact match to RHEL with only a few variations such as the removed the client for Red Hats support site integration and added a few things like AFS because their labs need it. The differences are well documented in the release notes and its a short list.
In addition SL guarantees long term patch availability even if Red Hat is no longer supporting that release.

CentOS tends to do thing like update the PHP libraries to make it easier for web developers. And as a result they take longer for many security patches because they occasionally hit dependency issues due to the packages they have updated.

-- Sent from my HP Pre3

On Jan 9, 2014 13:17, Orion Poplawski <[log in to unmask]> wrote:

On 01/09/2014 05:54 AM, Adrian Sevcenco wrote:.
> What technical differences would be between CentOS + scientific repo and SL?
>
> Just a personal thought, but maybe this would free some human resources
> for maintaining a lot of scientific (and IT/grid related) packages in
> well established repos (like epel, fedora/rpmfusion)
>
> Thanks!
> Adrian
>

Well, for me the main difference between CentOS and SL is that with SL you can
stay on EL point releases. That would require a major change in the CentOS
infrastructure to support it. Worth exploring though...

--
Orion Poplawski
Technical Manager 303-415-9701 x222
NWRA, Boulder/CoRA Office FAX: 303-415-9702
3380 Mitchell Lane [log in to unmask]
Boulder, CO 80301 http://www.nwra.com