Since we will all have to learn Longhorn for the next version of SBS, here is a place to start 

Windows Server Code Name "Longhorn" – Learning Portal

Windows Server Code Name "Longhorn" is the next-generation Windows Server operating system that helps IT professionals maximize control over their infrastructure with increased security, reliability, and flexibility.

E-Learning training

Collection 5934: Introducing Windows Server Code Name "Longhorn" (Beta 3)—Free for a limited time!
This online learning collection of five clinics introduces the new features and functionality in Windows Server "Longhorn." The courses cover server virtualization, security and policy management, branch office management, centralized application access, and server management. You can take the entire collection or just the courses that interest you.

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Clinic 5936: Introducing Security and Policy Management in Windows Server Code Name "Longhorn" (Beta 3)

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Clinic 5937: Introducing Branch Office Management in Windows Server Code Name "Longhorn" (Beta 3)

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Clinic 5938: Introducing Centralized Application Access in Windows Server Code Name "Longhorn" (Beta 3)

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Clinic 5939: Introducing Server Management in Windows Server Code Name "Longhorn" (Beta 3)

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Coming soon

Over the next few months, even more training content will become available, including discounted books and free sample chapters from Microsoft Press, additional e-learning offerings, and classroom training delivered by Microsoft Certified Partners for Learning Solutions.

Source: Windows Server Code Name "Longhorn" – Learning Portal