You might be right, but I think it's wrong to dismiss it just because it's hard to explain. Sometimes great new technologies are difficult because there is less to compare it to.
To be clear, I'm not dismissing it...I'm looking forward to playing with it. I just don't see my friends using it, and if no one I know uses it, why would I?
Also to be clear, their stuff is truly beta which is why they are limiting the users to a small set of developers. Sometimes while using the site you'll get a 500 error that will force you to refresh the browser page.