A First Look at Exchange 2010

The Future for Exchange Clients
It's long been standard practice for Microsoft to release a new version of Outlook alongside a new version of Exchange. Exchange 2010 is part of the Office 14 wave, so Microsoft will upgrade Outlook, Outlook Web Access, and Pocket Outlook (on Windows Mobile 7.0 clients) to add new features, improve usability, and accommodate the architectural changes in Exchange 2010, including some performance improvements within Outlook to deal with the demands of very large (>2GB) mailboxes. After all, there’s no point in Exchange being able to support very large mailboxes if its premier client finds it difficult to process those mailboxes, which is often the situation today.

The biggest thing you’ll notice in the client UI is a focus on conversation views where you'll be able to process complete sets of messages that make up a conversation more efficiently than you can today. MailTips, small balloon-like messages, will appear to warn users whenever an action might not make sense. For example, you’re about to use Reply to All on a message that includes 3,000 recipients. Other tips will tell users when recipients can’t receive messages because their mailbox is full or if they're out of the office and won’t be able to respond. OWA will also support MailTips and conversation views.

The Exchange 2010 Environment
Microsoft plans to release only a 64-bit version of Exchange 2010 for production, but they might again provide a 32-bit test version. Of course, now that Microsoft has Hyper-V in its armory, you can expect that Exchange 2010 will be a good candidate for virtualized deployments, albeit with the normal caveats that roles such as Client Access and Hub Transport are more suitable for virtualization than high-end Mailbox servers. Unified Messaging servers remain a poor choice for virtualization because of the demands of audio processing for voicemail. Given that experience with virtualization grows all the time, it’s wise to check with Microsoft for the latest news on support for your favorite application.

Exchange 2010 isn't supported for Windows Server 2003, so you'll have to deploy it on Windows Server 2008. As usual, Exchange 2010will have other prerequisites, such as the latest version of the .NET Framework, PowerShell 2.0, and some schema updates for AD. There's no current dependency that Exchange 2010 must access AD on Server 2008, but you'll need to ensure that your forest is at least at Windows 2003 functional mode and that there's at least one Global Catalog server running Windows 2003 SP2 in each domain that supports an Exchange 2010 server. Exchange 2010 doesn't support read-only domain controllers.

Within an Exchange organization, you can mix Exchange 2010 servers with servers running Exchange 2007 SP1 or later and Exchange 2003 SP2 or later, but there's no support for earlier versions of Exchange. Just like Exchange 2007, you won’t be able to upgrade an existing version of Exchange to the new release and will have to deploy new servers running Exchange 2010, then use the Move Mailbox feature to move users to the new servers. Details of deployment recommendations are still being worked out, but I expect that best practice will be to deploy servers running the Hub Transport (and Edge Transport) and Client Access roles first, followed by Mailbox servers.

Tons of New Developments
There are many other changes in Exchange 2010. Public folders persist, but some APIs (e.g., CDOEX, WebDAV, ExOLEDB) are replaced by Exchange Web Services. Unified messaging gains features such as a message waiting indicator and a personal auto attendant that can configure rules for how to answer incoming calls. You can expect Microsoft to connect Exchange better with Office Communications Server and its Windows Rights Management Services, bringing different strands of its information worker strategy closer together.

Microsoft still has tons of work to do before Exchange 2010 becomes a shrink-wrapped product, but all indications from the beta versions are that the new release will deliver some interesting and valuable functionality. Like any release, things can change before Microsoft ships the final software, including the elimination of features that don’t meet goals for functionality or quality. However, given that Exchange 2010 doesn't represent the same kind of generational change represented by the move from Exchange 2003 to Exchange 2007, I expect that the bulk of the functionality that exists in today’s builds will appear in the final release. The changes in the new version collectively represent nearly three years’ hard work by a large development group, so you can expect to be busy learning all about Exchange 2010 in the coming months.