Well I don't really agree that quantum computers are useful! Not yet anyway.

But in (most) distributed models of computing, networks of computers share bits back and forth. The quantum distributed models have computers sharing qubits. So this seems to be a practical implementation of a system that could solve certain problems (specifically some graph labelling problems) more efficiently (specifically, in fewer message-passing rounds).

Perhaps you're confusing "internet" (a network of computers) with "world wide web" (a set of linked documents)