While there may be problems with the original article I think that you are far wider of the mark than the author. Several times in your comment you have taken the behavior and practices of large-scale participants and tried to extrapolate these down to the small-scale players who make up the bulk of the users in these various systems. This is the sort of mistaken assumption that just earned someone a Nobel prize in economics ( * ) and it is probably one of the problems we had when building Mojo Nation. There are some things that are metered in bulk but which make no sense to do so at the smaller scale at which the consumer encounters them, and the nature and scale of these bulk goods can change quite quickly.
When we started work on Mojo Nation many were still on dial-up and even those with broadband connections had large asymmetry between the upstream and downstream bandwidth; trying to take advantage of this asymmetry was the genesis of our peer-swarming idea and what we had hoped would distinguish us from systems like Napster that had problems with large media files (aka pirated movies) when you were no longer in a college LAN environment. When you are considering something like bandwidth or local storage capacity from the perspective of cloud computing providers or ISPs then it is most certainly a resource that has a cost and which is closely metered, but for individual users their point in time bandwidth is effectively unmetered. No one is checking their current monthly usage statement before firing up Netflix, nor are they worried too much about the storage costs of holding on to a download for another few days so that they can improve their seed:leech ratio.
For most Americans water is effectively too cheap to meter. Electricity and fuel for heating are close to this level. Yes, before you point it out I am talking about the fat middle of the usage graph and not the extremes of either usage at one end or poverty at the other; for the vast majority there is very little thought given to cost when deciding to turn on a light or to take a shower. At various points in time people have had to pay close attention to their bandwidth usage or local storage capacity, but currently most people can ignore usage for daily tasks even when considering mobile bandwidth.
Clay Shirky was quite correct in pointing out that the transaction cost, both in clearing the transaction within the system as well as the mental cost to the user in just needing to think about the cost, was going to be a problem for us. There were a whole host of other issues related to general complexity of the system, too many knobs for users to tweak and/or use to game the system, and our desire to build a persistent storage system rather than an ephemeral file sharing tool, but this transaction cost was a non-trivial problem that we put off for too long. In the end the closest we came to trying to eliminate the mental burden and lower systemic clearing costs was to use Paris Metro pricing (e.g. you paid to move to the front of the queue, but if you were willing to wait for your bits the cost was 0.) This model has obvious problems when dealing with persistent storage that we were never able to work around, but it is easy to see the leap from this system to the tit-for-tat that Bram eventually landed on for handling ephemeral file sharing.
While it is possible to look at seed:leech ratios on major trackers as metering, this is a generous definition of the role of these ratios and they are much closer the the reputation-backed personal promises/tokens that Mojo Nation started with than to any actual currency. The goal of such ratio systems is incentive engineering, not strict accounting.
And to end this on a minor diversion that ties directly to your offhand dismissal of Enron in all this, I will point out that at one point Enron’s bandwidth trading group had enough interest in Mojo Nation to fly me out to Houston several times for meetings. A plush corporate palace with a pimped out Harley-Davidson in the upper-floor lobby of a group supposedly trading bandwidth should have been a sign of their upcoming fall, but at the time I was young and easily impressed…
( * ) Yes, I know that the economics prize is not, strictly speaking, a Nobel prize...