It is written improperly. It attempts to use the tr.im bookmarklet to shorten the URL (indeed the author didn’t even have the courtesy to use the tr.im API). API like traffic for tr.im must use the API, that is what it is there for. Additionally it wouldn’t work even if he had written it improperly because he doesn’t understand how some URL shorteners such as tr.im work.

The author has refused to fix his wordpress plugin and remove tr.im. It has generated an enormous amount of traffic to a free service that we pay for out of our pocket. As a result tr.im is banning any traffic coming from a blog using this plugin. This will slow down your pageloads for several seconds before it times out on its connection to tr.im.