One of the complaints about Google is that it's difficult to launch products due to bureaucracy. I'm starting to thing that's not a bad thing. If they'd done a careful analysis of the cost of jumping into this url-shortener bandwagon, we wouldn't be here. Maybe it's not a bad thing they move slower now.
I would bet that the salaries paid to the product managers behind shutting this down, during the time they worked on shutting it down, outweigh the annual cost of running the service by an order of magnitude.