Today's ubiquitous URL shorteners have seen a dramatic increase in popularity the last couple of years – much of it driven by the rise in popularity of Twitter itself. They are great for keeping character count at a minimum or to make sharing easier. Some even bring a few unique features to the table, like enabling statistics or the ability to select your own keyword, but as convenient as shorteners are they also introduce some new issues.
There's significant variance from one service to another when it comes to uptime, for example, while on the other hand given that the process involves using an HTTP redirect there’s also the latency issue. But perhaps more importantly is the fact that they obscure the target address and thus may be used to trick users to an unexpected destination.
