Need Assistance with Linux script on CentOS or Redhat

Hello:

I am fairly Junior Admin.

We have a handful of CentOS Systems on our network and I would like to create a script (shell or perl) that will ssh to the other systems and grab the list of possible updates, but not actually update them. I just want to create a report that list the updates on each host.

So instead of doing sudu yum update on each box, I kick off a script that will do it on all and create a report that looks like:

host1 has the following updates available:
=============================================================================
Package Arch Version Repository Size
=============================================================================
Installing:
kernel x86_64 2.6.18-53.1.14.el5 updates 15 M
kernel-devel x86_64 2.6.18-53.1.14.el5 updates 4.9 M
Updating:
asciidoc noarch 8.2.6-1.el5.rf rpmforge 892


host2 has the following updates available:
=============================================================================
Package Arch Version Repository Size
=============================================================================
Installing:

nagios-plugins x86_64 1.4.11-1.el5.rf rpmforge 1.3 M
net-snmp-libs x86_64 1:5.3.1-19.el5_1.4 updates 1.2 M

etc, etc...

So far, this is what I have:

#!/bin/bash
##
CNT=1
until [ $CNT -eq 10 ]
do IP=192.168.1.$CNT
REMHOST=`ssh root@$IP -C hostname`
echo "Host $REMHOST at IP $IP returned the following result:"
ssh root@$IP -C yum update | tee list_of_updates
CNT=`expr $CNT + 1`
done

Here are parts I don't know how to do:

1) get the script to automatically respond with "N" after yum update is run on each system and continue to the next host.

2) strip the data I don't want after each scan. There is gobs of data from running yum update, but I only want the data after:
=============================================================================
Package Arch Version Repository Size
=============================================================================

3) get the "Host $REMHOST at IP $IP returned the following result:" to append to the list_of_updates  report after each host is finished.

Your help is really appreciated.