It seems like RHEL 6 got the redhat-lsb split from Fedora, but someone forgot to ship the extra sub-packages:
# yum install redhat-lsb-graphics
Loaded plugins: refresh-packagekit, rhnplugin
This system is not registered with RHN.
RHN support will be disabled.
Setting up Install Process
No package redhat-lsb-graphics available.
Nothing to do
See also bug 585858 for some bugs in the Fedora packaging that we don't want copied over. :)
This request was evaluated by Red Hat Product Management for inclusion in a Red
Hat Enterprise Linux major release. Product Management has requested further
review of this request by Red Hat Engineering, for potential inclusion in a Red
Hat Enterprise Linux Major release. This request is not yet committed for
graphics and printing are in the optional repository. This was accidental, and is fixed for future milestones.
Please clone bug 585858 separately.
I've added bug 586260 as a clone of bug 585858.
Fixed in RHEL6.0-20100428.3
redhat-lsb-graphics-4.0-2.1.el6 successfully installed on RHEL6.0-20100428.3.
Red Hat Enterprise Linux 6.0 is now available and should resolve
the problem described in this bug report. This report is therefore being closed
with a resolution of CURRENTRELEASE. You may reopen this bug report if the
solution does not work for you.