In the latest builds of Windows Mobile, there have been a few improvements. One of the major changes is the updated Outlook client on device.
Microsoft have said theyâ€™re serious about on device updating and this is appearing in the Outlook client now.
As of yet, this seems fairly meaningless, but is at least a sign of things to come.
There is also a change to the UI, with threaded email that has long been available on desktop versions of Outlook (and web email services like Google Mail) coming to the mobile space,
Microsoft have also made it easier to add new accounts, with a quick picker for common email accounts much like some of the HTC enhancements to Windows Mobile.
This new update to Outlook is available in the latest builds in the 235XX tree, available on XDA-Developers (including for the Diamond, here).