Enterprise Desktop and Mobile PC replacement rates continue to lengthen while Tablet usage driven by BYOD is exploding.  These trends are placing IT management in an unprecedented vulnerable position as responsibilities and authority are no longer in balance.   This report analyzes the historical, current, and future influences that drive PC and Tablet adoption.  In addition to Sales and Installed Base Unit forecasts, this reports includes forecasts for Average In-Use Life for all platforms, as well as Tablet-PC cannibalization rates.    IT managers that have in influencing, voting, or vetoing role in Tablet, Desktop, or Mobile PC purchasing decisions need to read this report to gain a better understanding of the dominant market forces shaping future platform sales and installed bases.