Some nice words on this blog:

Unified Messaging: We have also taken the plunge and are currently piloting Exchange Server 2007’s Unified Messaging feature, which was one of the major drivers behind our Exchange 2007 implementation.  To say that we’re extremely pleased with the solution would be an understatement. We’ve rolled this out to some members of the IT staff and to just a couple of people outside the IT organization.  We are working on nailing down a couple of minor issues, but the feedback from the IT staff and even the outside people has been overwhelmingly positive, with one executive assistant saying to me after just two days of use “I don’t know how I lived without this.”

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If you’re an Exchange shop already and are still using a legacy voicemail system, in my opinion, UM alone is enough of a reason to upgrade, if you were considering doing so anyway.

While I love constructive criticism because it helps us make the product better, it's always nice to hear nice words like these as well :-)