If you are in a Virgin fibre area and you are a heavy internet user it is unbeatable. We just moved and lost our XL package but it was fast, reliable and great support when needed. Would go with them again if in a fibre area. BT's new fibre rollout covers pretty much the same area and sky will use that but it is late and still not as good as virgin speeds. We are using plusnet now and they were excellent to deal with. Different call packages to choose from and data bandwidths, but no telly. I would ask what channels you really want? Can you get the content any other way?
I advised my parents to get plusnet but they went for talktalk and after 3 months and many phone calls by them and myself and still do not have the service connected. Not impressed with their support at all.
Paul_B have you thought about a £200-£220 netbook? I've got one that is great to use and plan on taking next time I'm camping out. Plan on using the dongle to be really sad and upload photos whilst out! My model when fully charged should last 10 hours, with a dongle and slot for the memory card from my camera and weighs 1.2 kg. If i get on alright will post back here.