Don't worry about it. It was mostly people going nuts about something they didn't understand. The Quality of Service bandwidth reservation only withholds bandwidth if a QoS-aware application requests it. Otherwise, it just sits there idling. It's unlikely you'll ever encounter an application that does this unless you're specifically trying to use such a feature. When such an application makes a request, the QoS system only reserves the amount of bandwidth the application requests, with a limit of 10% by default. So if the app only wants 1% reserved, then it only reserves 1%. This is also only applied to your LOCAL bandwidth. If you have a 100Mbps Ethernet connection, then 10Mbps is reserved by Windows. Your Internet connection is not affected by this if you use a router type device, since the router is still having to buffer your requests and slow down your connection since your Internet connection isn't able to keep up with it anyway. Even with a direct connection to a cable or DSL modem, that's a 10Mbps link, so only 1Mbps would be reserved. But, only if an application requested it.
If you want to be paranoid, you can look at the properties for your Local Network Connection, and uninstall the QoS Packet Reservation. You can also go into the Services tool in Administrative Tools (as an administrator account) and disable the QoS RSVP service.