Just read through the virtualization info today and found the interesting post regarding SAP internal is going to virtualize with Citrix XenServer. I will not copy the full story as you can read more from here.

As the article stated, there are 500 machines which will be virtualized in Citrix Xenserver, are not be used in production environment. Those machines are development, test and training environment for SAP internally.  We know SAP is 1 of the heavy user for VMware since years back. A move to Citrix  Xenserver did surprise myself, but obviously it does provide more choice to SAP internal.