Are looking for running MAC OSX in Virtual world say XenDesktop or any other VDI?
To start with your way in this, you need to have a valid licensing model from Apple to run MAC OSX in virtual environments.
However, from the latest EULA of Apple MAC OSX, Apple license does support virtualization of MAC OSX but is limited local to that MAC OSX box and for very non-commercial purposes.
Below is the excerpt from the latest MAC OS X Mountain Lion 10.8.2 EULA.
“(iii) to install, use and run up to two (2) additional copies or instances of the Apple
Software within virtual operating system environments on each Mac Computer you own
or control that is already running the Apple Software, for purposes of: (a) software
development; (b) testing during software development; (c) using OS X Server; or (d)
personal, non-commercial use.”
One need to check with Apple on Volume licensing options to understand their licensing models for virtualising MAC OSX systems, for Citrix XenDesktop or any other VDI solutions.
Refer to the Apple’s MAC OS X EULA document for current latest Mountain Lion version 10.8.2.: http://www.apple.com/legal/sla/docs/OSX1082.pdf