They've missed a trick here. Many customers will be tied into contracts with their existing providers and be unwilling to change just to use this service - what's the point if half of your most highly-paying customers can't access the value added features they deserve? Seems a bit rich.
No doubt their justification is that they'll do some BT Vision style QoS prioritisation to give an assured minimum throughput for the digiboxen, but it still sucks that for people on decent ADSL / ADSL2+ (e.g. Be / O2) who are paying the premium amounts to Sky for telly won't be able to use this.
Paris, because even she knows when she's getting shafted