Harold Wong has posted his latest slide decks for Exchange 2010, presented during the Exchange 2010 Launch Tour. The links listed below were taken from Harolds blog here;
Introducing Exchange Server 2010
Exchange Server 2010 Unified Messaging
Exchange Server 2010 High Availability
Exchange Server 2010 Archiving and Retention
As ever, let me know if you have any questions.
This is excellent -- thanks very much!