This post has certainly generated alot of good comments. I have represented both the circuit breaker and fuse manufacturers in my past. I think the important thing to take away is that both fuses and circuit breakers can provide proper protection if proper maintenance and (testing for circuit breakers) are performed. Any device can be misapplied or improperly maintained. In addition, a fuse or circuit breaker may be better suited for a specific application. However, in my opinion there are less "concerns" with fuses compared to circuit breakers over the life cycle of the device.
With regards to the future of circuit breakers and fuses, I think we will see much improved features and protection from both devices.
With regards to arc flash protection, Ryan J appears to have picked a situation where a cirucit breaker can provide better arc flash protection. One caution here, what is the device type and ampere size...there really isn't enough information in his post to determine the application. With arc flash protection the, fault current, arcing fault current, type and size of the device has a great impact. There can be cases where a circuit breaker can be shown to provide better protection than a fuse, however, in general, I would argue that a fuse will provide better protection in the majority of cases. Another consideration can be the reliablity of operation. With circuit breakers you are relying on an expected response time that can only be confirmed with proper maintenance and testing.
