Some elements of his vision totally resonate: open; reduced barrier to entry in creation of content; platform of solid tools.
Some things remain a little sketchy: Compelling content is needed to drive a good platform – this is still unproven; Do consumers want to search through thousands of worlds like they do thousands of casual flash games vs. going to somewhere with a compelling single game/community experience like World of Warcraft?; Can they actually implement certain elements of the vision – especially a 3D client and make that work within the vision?
What is for sure is that it is a more ambitious and thoughtful approach to virtual worlds than any other company I’ve seen right now. So it’s a watch this space.