MS Exchange Team has recorded the Exchange 2010 webcast, now all these recordings are available on demand.
TechNet webcast: Storage in Exchange 2010https://www.livemeeting.com/cc/mseventsbmo/view?id=1032418920&role=attend&pw=6064172E
Exchange 2010 High Availability http://msevents.microsoft.com/CUI/EventDetail.aspx?EventID=1032416676&Culture=en-US
TechNet Webcast: Exchange 2010 Overview http://msevents.microsoft.com/CUI/EventDetail.aspx?EventID=1032416679&Culture=en-US
TechNet Webcast: Exchange 2010 Management Tools http://msevents.microsoft.com/CUI/EventDetail.aspx?EventID=1032416687&Culture=en-US
TechNet Webcast: Exchange 2010 Archiving and Retention http://msevents.microsoft.com/CUI/EventDetail.aspx?EventID=1032416694&Culture=en-US
TechNet Webcast: Exchange 2010 Architecture http://msevents.microsoft.com/CUI/EventDetail.aspx?EventID=1032416706&Culture=en-US
TechNet Webcast: Federation in Exchange 2010 http://msevents.microsoft.com/CUI/EventDetail.aspx?EventID=1032416724&Culture=en-US
TechNet Webcast: Exchange 2010 Voice Mail enabled by Unified Messaging http://msevents.microsoft.com/CUI/EventDetail.aspx?EventID=1032416726&Culture=en-US
TechNet Webcast: Exchange 2010 Information Protection and Control http://msevents.microsoft.com/CUI/EventDetail.aspx?EventID=1032416728&Culture=en-US
TechNet Webcast: Exchange 2010 Transition and Deployment http://msevents.microsoft.com/CUI/EventDetail.aspx?EventID=1032416708&Culture=en-US