Lamentablemente YUM no da la opción de listar la versión de los paquetes actuales junto con su actualización disponible de forma nativa, para ello se puede utilizar el siguiente script en bash.

yumupdate.sh

#! /usr/bin/bash
echo $'\n'
printf '%*s\n' "${COLUMNS:-$(tput cols)}" '' | tr ' ' =
TITLE1="Package current version"
TITLE2="Package new version"
let COL=$(tput cols)-${#TITLE1}
printf "%s%${COL}s" "$TITLE1" "$TITLE2"
printf '%*s\n' "${COLUMNS:-$(tput cols)}" '' | tr ' ' =
echo $'\n'
 
yum -q check-update| while read i
do
    i=$(echo $i)
    if [ "${i}x" != "x" ]
    then
        UVERSION=${i#*\ }
        UVERSION=${UVERSION%\ *}
        PNAME=${i%%\ *}
        PNAME=${PNAME%.*}
        PRIMERO=`rpm -q ${PNAME} --qf '%{NAME} %{VERSION} '`
 
        let COL=$(tput cols)-${#PRIMERO}
        printf "%s%${COL}s" "$PRIMERO" "$UVERSION"
    fi
done

Ejemplo de salida.

===================================================================================
Package current version                                         Package new version
===================================================================================

ORBit2 2.14.17                                                        2.14.17-5.el6
at 3.1.10                                                         3.1.10-44.el6_6.2
audit 2.2                                                               2.3.7-5.el6
audit-libs 2.2                                                          2.3.7-5.el6
audit-libs-python 2.2                                                   2.3.7-5.el6
authconfig 6.1.12                                                     6.1.12-19.el6
avahi-libs 0.6.25                                                     0.6.25-15.el6
bash 4.1.2                                                             4.1.2-29.el6
bfa-firmware 3.0.0.0                                                 3.2.23.0-2.el6
binutils 2.20.51.0.2                                           2.20.51.0.2-5.42.el6
bridge-utils 1.2                                                         1.2-10.el6
ca-certificates 2010.63                                          2014.1.98-65.1.el6
centos-release 6                                                6-6.el6.centos.12.2
chkconfig 1.3.49.3                                               1.3.49.3-2.el6_4.1
coreutils 8.4                                                            8.4-37.el6
coreutils-libs 8.4                                                       8.4-37.el6
cpio 2.10                                                             2.10-12.el6_5
...