Hello,
The Scientific Linux development team has put out a roadmap for the
future of Scientific Linux 4.

http://www.scientificlinux.org/distributions/roadmap

Scientific Linux 4 is going to follow the same type of roadmap that we
followed for Scientific Linux 3.

SL 4.9 will be a "legacy" release.  It will be supported until
the time that RedHat no longer supports RHEL 4, which is February 2012.
This release will only get minimal support, security updates only.  Red
Hat calles this "Production 3 Life Cycle Phase" which is

   "During Production 3, at a minimum, qualified security errata of
    important or critical impact and selected mission critical bug fixes
    may be released independent of minor releases.

    No new functionality, new hardware enablement or updated installation
    images are planned for release in Production 3 life cycle phase.
    There are no minor releases planned during this phase."

https://www.redhat.com/security/updates/errata/

SL 4.0-4.8 will be obsoleted.  Currently that is set to October 10,
2010.  That date is flexible.  We want to give users at least 6 months
to update to SL 4.9.  So if SL 4.9 takes too long to be released, we
will move the October date back.

Summary:
SL 4.0-4.8 : Obsolete in October 2010
SL 4.9 : Minimal support (security only) until February 2012

Thank You
Scientific Linux Development Team
-- 
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Troy Dawson  [log in to unmask]  (630)840-6468
Fermilab  ComputingDivision/LSCS/CSI/USS Group
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