Just happening to be downloading VMware Workstation today to run ESX 4.1 as a guest OS and lo and behold a new version came out today with official support for running ESX/ESXi 4.1 as virtual machines. Doesn’t look like there are any other major changes to Workstation besides the added support for vSphere 4.1 and some minor bug fixes. Download here and release notes are here.
VMware Workstation 7.1.1 is a maintenance release that resolves some known issues and adds the following new support. It is a free upgrade for all VMware Workstation 7.x users.
New Support for Guest Operating System
VMware vSphere 4.1 is now supported as a guest operating system. VMware Certified Professionals (VCPs) and virtualization experts can use VMware vSphere 4.1 to install the latest server virtualization software and experiment with server setup, conduct training, show demos, and test production configurations. Running ESX as a guest eliminates the need to have spare hardware available to run ESX natively and enables ESX to run on systems that are not listed on the ESX hardware compatibility list (HCL). For more information on the supported processors and host operating systems, see Considerations for Running an ESX Guest.
This feature is intended for educational and demonstration purposes only and should not be used in production environments. To use this feature, you must download VMware vSphere 4.1 from the VMware Web site and follow the installation documentation provided with VMware vSphere to install ESX.