As many of us know Blackberry service was interrupted this past week worldwide. Does this mean RIM is doomed? No, it does not. RIM relies on the BIS servers to function, these are RIM owned and operated. They are worldwide, and use a lot of capital every year to maintain.
When a switch in a system this size fails it causes a major backlog, which will cause a bottleneck in the system. This bottleneck cause things to function slower than normal, think of it like taking a hose and putting a kink in it. The water flows out at a lot slower rate than it did before flow was restricted.