Beginning in November, 2010, Microsoft solicited community input regarding its support of the core and most commonly adopted email and calendaring standards in the next versions of Microsoft Exchange Server and Outlook. The process confirmed the existing plan of support. Accordingly, Microsoft will continue to support the following standards in the next versions of Microsoft Exchange Server and Outlook:
IMAP: Internet Message Access Protocol version 4.1 (RFC 3501)
POP3: Post Office Protocol version 3 (RFC 1939)
iCalendar: Internet iCalendar Protocol (RFC 5545), the iCalendar Transport-Independent Interoperability Protocol (RFC 5546), and the iCalendar Message-Based Interoperability Protocol (RFC 2447).
If you have additional feedback on Microsoft Exchange Server and Outlook standards support, please visit the Microsoft Office feedback page.