Only if the QoS is tilted in favor of the popular stuff. The concern here isn't QoS in favor of the popular stuff... The concern here is QoS in favor of one particular brand of service X vs another. (e.g. Netflix vs. Hulu).
If QoS favors unpopular but more profitable services, it can make the user experience for those services significantly less crappy than the competing more popular services and actually drive shifts in consumer behavior towards the less popular services.
Of course, as this succeeds, it becomes self-defeating over the long run, but, only if your goal is to provide good service to your customers.
Absolutely agree. This goes back to my original comment on the thread in that having a content provider pay for higher priority gives a financial incentive to the network to create congestion (or allow such congestion to occur during the course of normal bandwidth consumption increases over time) in order to collect that revenue. But there is a potential problem here in that content providers are producing applications and content requiring increasing amounts of bandwidth but are not bearing the cost of delivering that content to the end user. If the ISPs are directly peering with the content provider at some IX, the content provider gets what amounts to a free ride to the end user. They then release a new version of something that uses more bandwidth (say, going to HD video and then maybe 3D HD at some point) which puts pressure on the ISPs network resources. Do you then increase prices to the consumer in a highly competitive market and run the risk of driving your customers away, do you absorb the cost of required upgrades and run at a loss for a while only to see the applications increase in bandwidth requirements again? Do you try to get the content provider to pay for some of the "shipping" cost? In a pure transit model, the content provider's expenses would go up if they increased their bandwidth utilization which gave them a financial incentive to be innovative in ways of delivering higher quality with the lowest possible bandwidth consumption. As more people move to peering over public IX points, the burden falls on the ISPs internal network to deliver the goods and they have no control at all over the applications themselves. So bandwidth is practically "free" for the content provider and not so free for the eyeball provider. So where a content provider might be forced to upgrade from GigE to 10GigE links at exchange points (maybe adding a blade to a chassis), a service provider might be faced with congestion on potentially thousands of end user links and the gear that interconnect the PoPs. In that light I can see where they might want a fee. But a better way of looking at it is not in prioritizing anyone up, look at it the other way. Imagine an ISP says "if you don't pay us, we are going to prioritize your traffic down". So anyone who pays gets their traffic at the normal default priority, those who don't pay get in the "space available" line. Now a content provider who does not pay the toll sees a drop in users which equates to a possible drop in ad revenue. George