Internet2 is not at all looking to supersede the Internet. In fact, you'll find that it's actually based on prettymuch the same gear. It's just a very large internet (little i, not big I - meaning a generalized external network) linking universities and research facilities to facilitate the sharing of RIDICULOUSLY large datasets that otherwise would have to be loaded onto hard drives and shipped out on a truck or something. Sure, occasionally there's other traffic being switched in from other networks (and occasionally the Internet) but I2 still isn't an extension or replacement for the current Internet.

It's a totally distinct network. And the amusing thing is that most bandwidth-increasing research being done on I2 is to facilitate larger data transfers for OTHER research. The results could be deployed to the Internet, but first somebody has to pay to install it.