A number of people think QoS was interesting for a while but that its never either found its true use or is dead.
There are unresolved questions from a customer point of view as to what they are actually going to get, what difference it will make and how they can measure their performance and the improvements from QoS.
Having worked for a pretty large, now bankrupt, Netherlands based operator - where we where looking at QoS what we concluded was that a) QoS mechanisms are for the local-tail. Backbones should have "enough" bandwidth (and bandwidth is cheap). b) QoS was for customers with services like VoIP and VPN - and in most cases they where needed becuase the end users refused to buy the bandwidth they actually needed. c) The QoS implementations in the vendor boxes at best leaves a lot to whish for and in most cases simply does not work (but to their credit they where really helpful in working with us on this). - kurtis - PS. Notice that I left out the M... word. :)