Doesn't quite follow the MVC pattern but I would put meteor on par with Ruby On Rails.
Is it something I can host anywhere or only on Meteor servers?
Yes. You can host it on your server. It isn't well documented or supported(to me), however.
The demo is neat, I get that - but what is it?
I am not sure what you're trying to ask here.
Runs on handlebars.
For someone like me, who's used to the standard LAMP stack and hasn't played with Node, any of the js frameworks, redis, or handlebars, it took a few days to get acquainted, but once I did I really enjoyed using it.
Again, a little too much magic, which makes me feel like my code is weak.