The microsoft exchange team are releasing exchange 2007 service pack 2. One of the primary features that I like about service pack 2 is the fact that it will extend the 2008 windows backup feature adding in the option to allow for exchange backups of given storage groups. Currently this is impossible using an integrated windows tool as NT Backup is not a part of server 2008. They have also added additional public folder control via powershell.
Exchange 2007 Service Pack 2 will be required in order to migrate a Exchange 2007 server to Exchange 2010.
For more information, please see the Microsoft Exchange team blog: