Windows Server 2008 certifications were developed in new generation model of certifications with careful attention to current server-related job roles. There is no MCSA or MCSE on Windows Server 2008, however, your MCSA and MCSE on Windows Server 2000 or 2003 are not retiring, expiring, or in any way de-prioritized.
Starting Fresh (No Upgrades):
MCITP: Server Administrator (3 Exams):
70-640: MCTS: Active Directory, Configuring
70-642: MCTS: Network Infrastructure, Configuring
70-646: MCITP: Server Administrator
MCITP: Enterprise Administrator (5 Exams):
70-640: MCTS: Active Directory, Configuring
70-642: MCTS: Network Infrastructure, Configuring
70-643: MCTS: Applications Platform, Configuring
70-620: MCTS: Vista or 70-624: MCTS: Deploying and Maintaining Vista and 2007 Office System Desktops
70-647: MCITP: Enterprise Administrator
MCITP: Server Administrator and MCITP: Enterprise Administrator (6 Exams)
70-640: MCTS: Active Directory, Configuring
70-642: MCTS: Network Infrastructure, Configuring
70-643: MCTS: Applications Platform, Configuring
70-620: Vista or 70-624: Deploying and Maintaining Vista and 2007 Office System Desktops
70-646: MCITP: Server Administrator
70-647: IT Pro: Enterprise Administrator
Upgrading from MCSE 2003:
MCSE 2003 to MCITP: Enterprise Administrator (3 Exams) -
70-649 (Upgrade) + 70-647 (IT Pro: Enterprise Administrator) + (choose one) either 70-620 (Vista) or 70-624 (BDD).
MCSE 2003 to MCITP: Server Administrator (2 Exams)
MCSA 2003 +
70-649 (Upgrade) + 70-646 (IT Pro: Server Administrator)
MCSE 2003 to MCITP: Server Administrator and Enterprise Administrator (4 Exams):
70-649 (Upgrade) + 70-620 (Vista) or 70-624 (Deploying and Maintaining Vista and 2007 Office System Desktops) + 70-646 (IT Pro: Server Administrator) + 70-647 (IT Pro: Enterprise Administrator)
Upgrading from MCSA 2003
MCSA 2003 to MCITP: Enterprise Administrator (4 Exams)
70-648 (Upgrade) + 70-643 (MCTS: Application Platform) + 70-620 (Vista) or 70-624 (Deploying and Maintaining Vista and 2007 Office System Desktops) + 70-647 (IT Pro: Enterprise Administrator)
MCSA 2003 to MCITP: Server Administrator (2 Exams)
70-648 (Upgrade) + 70-646 (IT Pro: Server Administrator)
MCSA 2003 to MCITP: Server Administrator and Enterprise Administrator (5 exams)
70-648 (Upgrade) + 70-620 (Vista or 70-624 (Deploying and Maintaining Vista and 2007 Office System Desktops) + 70-643 (MCTS: Applications Platform, Configuring) + 70-646 (IT Pro: Server Administrator) + 70-647 (IT Pro: Enterprise Administrator)