That distinction exists out in conceptual space, yes. But I am not sure Last.fm falls on the right side of it. A startup can only live on "hey that's cool" for

That distinction exists out in conceptual space, yes. But I am not sure Last.fm falls on the right side of it. A startup can only live on "hey that's cool" for so long, when the promise of all these new ways of interacting is itself suggestive enough to capture people's imaginations even if it happens not to be very useful. But soon we get acclimated, and even bored. And to keep pace with the ever-receding limit of human curiosity there must be some combination of new innovation and enduring usefulness, if not just one or the other.