Just what I was looking for! Rated 5 out of 5 stars
While I understand the need for short URLs, a lot of information is lost when all you can see is http://bit.ly/sfasdfdks. Before clicking a link, I generally like to know where I'm going (what domain), especially if all someone says is "Check this out!" I thought this might be the perfect application for an add-on and, low and behold, here it is!
This add-on works exactly as advertised. Find any one of a number of different varieties of shortened URLs on virtually any webpage, hover over the link and within a second or two you get a little box with the expanded URL and the title of the destination page. There's also a link that takes you to some additional useful information at http://longurl.org/expand?url=...
This add-on is very handy and never gets in the way. Load it up and forget it. Very well done!