The management pack called Microsoft Management Pack Notifier is very useful as you do not have to monitor the Microsoft sites to get the latest MPs. This MP will do the job for you. Unfortunately, it does not monitor report versions.
To benefit from it, first download and install the MSI package. It creates Microsoft Management Pack Notifier.akm (and an EULA and a readme) below %programfiles%\MOM 2005 Management Packs\Microsoft Management Pack Notifier.
It seems to be old stuff, now being released for the public. The file is dated November 11th 2004.
Next import this MP from the administrator console using the Management Pack Import/Export Wizard. Remember to select 'Import Management Packs only' or you may be stuck in the Wizard when you must specify report to import (you can though step back).
The MP creates a new rule group called Microsoft Operations Manager MPNotifier, creates a new computer group called Microsoft Operation Manager MPNotifier MOM Server. The rule group contains a rule that check the versions against microsoft.com. This rule has a provider called MPNotifier-Schedule daily which runs the Microsoft MPNotifier Version Check script daily. Another rule fires off an alert when the versions mismatch. Finally an alert rule forwards the alerts to the Operation Manager Administrators notification group. I do not know why, but on my RTM test system, it does not fire off any alerts - I only get events.
An event looks like this -
You must manually add the server you want to check microsoft.com for updates to the new computer group. Keep in mind that the agent account on the server in question must have http access to microsoft.com across any firewall in the path. The actual URL it uses can be found in the script and is http://www.microsoft.com/management/mma/momnotifier.xml.
Unfortunately, the XML does not provide a direct download link. Let us hope, that will be added in the next release. Ideally, it should provide the option of downloading the files and even upgrade the MPs. The latter for test environments only naturally ;).