Since I'm already a happy user of Linux at work and fortunate enough to have other means to access email, calendar, and other services traditional on a Windows infrastructure through workarounds and generally complex tricks, I'm quite interested in the developments on offering support for the Windows infrastructure in Linux.
I found out today about OpenChange a somewhat new project to deliver MAPI support in various tools by implementing MAPI in a library. Although this is still fairly new and probably not yet ready for any kind of production use, I'm definitely going to give this some effort and try to have it run... perhaps even contribute code to it?
In my opinion, OpenChange brings a promising "outlook" for the future to enterprises wishing to migrate desktops to Linux, without necessarily going through the lengthy and complicated process of migrating Active Directory domains, Exchange servers with millions of messages, and other features in use immediately. For enterprises, although Linux desktops seem a good idea for, among other things, alleviating licensing costs; most are not yet ready to scrap complex Windows-based architectures, and will instead wish to make good use of them until upgrade (or migration) is no longer avoidable.
On the bright side, although OpenChange is not quite ready, Evolution at least has come a long way since previous versions provided on Ubuntu repositories. Since Hardy, it crashes less often, and you can even actually see free/busy information for other AD users, when Evolution decides it wants to cooperate :)
On the same subject, now that Active Directory integration is available through the use of Likewise Open on Hardy, joining a machine to a Windows domain is easier than ever. The constant state of progress I'm noticing from all distributions, but especially Ubuntu on the subject of Windows integration definitely gives me a lot of hope for the future.