In addition to the difference in targeted bandwidths, the primary difference is that SuperNet is a testbed that promotes networking and communications research. While NREN, vBNS, DREN AND ESNet are production network supporting advanced application. SuperNet is a network that networking researchers can experiment on. Full peering and interoperability between SuperNet and 100x networks is expected. Any potentially service-affecting experiments will be need to be scheduled into the shared calendar for researchers.
Military relevance is a plus.