RIP tr.im (So that's how it ends)
blog.tr.im
blog.tr.im
With no clear business model except for a hope that someone buys them out, it was just a lottery ticket.
A business like a URL shortener is a particularly dangerous one, since if you succeed your costs skyrocket quickly yet you still have no business model. This forces people quickly to either sell or shut down. Even worse, you're likely to succeed at getting users since everyone knows what it is and needs one, tricking you into thinking you're succeeding when all you're doing is bleeding money.
If you're starting a business doing something that everyone loves and there are already 10 of them but you have no business model, you should probably stop right away unless you have some serious capital, preferably external capital.
There's gotta be at least another couple dozen of these failure coming in the future....
However, be ye warned: This is what happens when you base everything on somebody else, whether it's Twitter, Facebook, Google or whomever. They can crush you in an instant, and often it's just because you're too insignificant to matter to them.
Who wants to bet that in a year or two there'll be another few url shortening services down the drain, and millions more broken links out there on the net.
I do hope they open source it. That client had the most potential from the native Mac ones that I've tried.