Then I copied the resulting url (http://www.magicbeef.com/)

After pasting it in google service, it produced a different short url: http://goo.gl/YH1c

I first assumed that every destination would render an unique short url, but thats not the case. This way google knows the full stats of http://www.magicbeef.com/. But you can only know the real stats if you know ALL the short urls pointing to it. :)

EDIT: I my short url stats page theres a notice: "119 total clicks on all goo.gl short URLs pointing to this long URL"

EDIT: Notice the browser stats of the link (http://goo.gl/info/Jvhu) Almost NO IE. Also less than a half windows.