A ton of things have been happening in the Exchange world that I've not been keeping up with very well, but I did come across two items that were of particular interest to me that I thought I'd share.

First, the MS Exchange Team has put up a blog item discussion a feature of Exchange that's been around a long time (Single Instance Storage).  SIS is a technology that was introduced in Exchange 4.0 that allows for an email to only exist once in the Information Store for multiple different users (if those users are on the same system).  So if an email (especially an email that contains attachments) is sent out to 10 different users, the Exchange server will only keep one copy of the email and all users will reference that copy.  There are some changes with SIS in Exchange 2007 namely that it only performs Single Instance Storage of message attachments, not of message bodies.  This makes perfect sense when you think about it considering that most of the storage that you'll consume on your Exchange server is related to attachments more so that simple text.  Simple text is small and generally irrelevant whereas attachments kill you.  This is particularly true since 90% of the organizations I've consulted for seem to think that Email = File Server.   You can read further about the reasons why the Exchange Team made this decision in the blog post here.  Ultimately it came down to a trade off between storage savings and IO Operations.  Ultimately storage is cheap, IO is not.

The second thing I want to cover in this blog item is a discussion about the newly released Office 2008 for the Mac and Entourage (the Outlook equivalent for you the non-Mac people out there.  Office 2008 for Mac is a completely new beast versus Office 2004 for Mac.  Luckily Amir Haque from Microsoft has written about many of the new features in Entourage 2008.  The two part blog item can be found here:  Part 1 and Part 2.  An excellent read.