A standalone copy of the Exchange 2007 SP1 Help file (CHM) has been made available for download here http://www.microsoft.com/downloads/details.aspx?FamilyID=5eb0f9a0-2c49-4f2a-8a09-b981ed667821&DisplayLang=en

This contains information on monitoring Exchange 2007 with Operations Manager 2005 (see the Operations/Monitoring and Operations Management section). The information in the help file is also relevant to the Exchange 2007 MP for Operations Manager 2007 as it is a converted MP.