I personally don't pay for Live because I personally don't ever play online. However if I did I would play on Xbox Live. Its easily the best online service I have ever used in terms of latency, features and ease of use.
If there was a comparable single service which did everything Live does in the one package just as well and cheaper, then I would feel that Live was over-priced. At the moment it is the one single premium online service that I can see on any platform whether it be PC or console.
From what I understand one of the upcoming improvements to Live is going to be an improvement in voice chat quality. Since voice chat is done be a server they would probably have to beef up that capability considerably. It will also increase the bandwidth demands across the whole of the network.
Tease.
