This post is a must-read for every Exchange administrator and Outlook IT Pro who deals with Exchange connectivity.
From an end-user perspective, this change will offer faster reconnections to the Exchange server when for instance resuming from hibernation or switching between a wired and wireless connection. In the future, it will also offer support for native multi-factor authentication for Exchange accounts.
Support for MAPI over HTTP will be made available to Exchange Online (part of Office 365 for Business) customers later this year. Outlook 2010 will also get support for MAPI over HTTP connections in a future update.