This is a nice convergence of technology, and very cool and all, but am I the only one who is really bugged by them calling this "your own cloud system"?

"The Cloud" != "a webserver". This is a Javascript desktop with a PHP backend. It could run on a virtual server in a cloud, but that's not even the way they sell it. It's not even sold as an app service ala Google Apps.

Also, check out CorneliOS: http://www.cornelios.org/. Similar deal, but built in Perl.