hmm.. need to find another rickroll for the docs then
(that'll teach me to try to be funny)
anyway, 2.1.0 beta 3 should work...
If you see the message "loading something from default" it usually means the oEmbed provider is unknown to the script... in which case the default http://oohembed.com/oohembed/
will be used as a fallback.
Sometimes the resource you link to is unavailable to anonymous (ie. not logged in users of youtube) .. and then nothing will be returned from an oEmbed call.
If nothing is found then, nothing usefull will be shown, I'll probably need to work on that.
What resource did you try? (as hansfn mentioned, the classic rickroll in the readme is unavailable in some countries)