KB 2009942 - Exchange 2010 support for UDP notification - good news for Outlook 2003 clients
Exchange 2010 SP1 RU3 (KB 2492690) was released today.
Mentioned in the release notes is an update (KB 2009942) that will make the online Outlook 2003 experience closer to the Exchange 2003/2007 experience, due to UDP notification support returning.
This eliminates a potential deployment blocker for organizations moving to Exchange 2010. Great news overall!