VMware seems to have ditched the product name “3i” and silently introduced “ESXi”. I noticed it when the download page was updated today. But you can also read it on the “product section” of the VMware website. I think this is a better name instead of differentiation in versions, keeping the versions alligned and changing the name makes more sense to me and probably most customers.
Besides this they’ve also ditched the “server” part in VMware ESX Server, for more info check out the blog by John Troyer!