Ebook: Microsoft Exchange server 2010 unleashed

Very, very disappointed by this book.
The editing was just plain shocking, in several instances it uses the incorrect version of Exchange, eg, Exchange 2007 introduced the Unified Messaging Role and Exchange 2007 has built on that
In the section on securing Exchange with ISA the author uses the wrong product altogether changing Exchange 2010 for SharePoint.
The book is about 500 pages too long as well. Every time a concept is discuses it seems that the authors felt the need to define it EVERY TIME. This lead to me skipping large portions of the book because it had already been discussed in earlier chapters.

I would recommend getting the Pocket Administrators Consultant as that is a significantly better book.