Thank you Damien for pointing me to this article explaining why you should thin twice before deploying Exchange 2013....

Exchange Server 2013 reached RTM a couple of months ago and has since reached General Availability (GA).

In my personal opinion, Exchange 2013 RTM is not ready for prime time. Microsoft made a decision to release all of Wave 15 (Office desktop applications and servers) at the same time; as well as release Windows 8, Windows RT, and Windows Server 2012 at the same time. I think this decision was seriously flawed. It is obvious that the products were not complete at RTM (witness Windows 2012 and Windows 8 having 300 MB of patches between RTM and GA, and Exchange 2013 not supporting any interop with prior versions of Exchange at either RTM or GA). It is easy to conclude that the RTM dates were artificially imposed.

I have prepared a class on Exchange 2013 for one of my clients and part of that class was to discuss the limitations associated with Exchange 2013 RTM when compared to Exchange 2010 SP2. Note that the rest of the class discussed many of the new features and capabilities that have been added to Exchange 2013. So... the story is not all bad.

But as a summary of my opinion, Exchange 2013 RTM is not ready for prime time. Right now, it can only be installed in a green-field environment (that is, an environment where Exchange did not previously exist), so it is a safe bet that the Exchange team agrees with that as well. We can hope that some updates will quickly come out to address some of the current deficiencies.

This list is by no means exhaustive. And, as always, whether a particular issue is important to your organization requires you to evaluate your environment.

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