Google has its own virtual world simulator. Lively. Read about ita t terra nova blog.
I made a room ( a cafe!) and an avatar. My avatar looks like one of my smug students chewing gum. Blech.
I couldn’t seem to walk, only scoot by clicking on a different spot and then the ava just **zip** appears there. For some reason it reminded me of a 3D version of the old text adventure games like Hitchhiker’s Guide or (??) Zork.
Ok, thats my review after five minutes. It was easy to download and set up.