Come spesso, non ho tempo di tradurre il pezzo.
URL shorteners are "cloud" services that do basically one thing: they take a long URL (such a web address) and transform it into a short one. They became popular with the explosion of microblogging facilities like Twitter, Identi.ca, Facebook et al.
Today "@AndyC", who is a UK person that posts a lot on Identi.ca, ranted about URL shorteners, and about a new one called ow.ly. He wondered what in heaven could be their business model, and I discovered some not-so-good things. That ignited me to write a little bit about them, hoping to receive more feedback and provide more reasoning later.