I have an ESX 3.5 host running on an ML-110g4 that I want to upgrade to the beta of vSphere.
The vSphere client seems to come with a remote update utility as shown below.
The rest on :
http://vinf.net/2009/04/22/remote-in-place-upgrade-from-esx-35-to-vsphere-esx4/
It was done with a beta release of vSphere also...
