I think the real issue is not whether cable viewers will lose Sky one or not, as it seems pretty certain that to pull that would be a pretty stupid move on Sky's part, or the premium channels (movies, sport etc) which they have to provide, but more whether they will start sharing their HD content. Currently they don't and in the current bad atmosphere are unlikely to soon. All they have to do is not share it with Virgin and sit and wait for customers who have all gone out and shelled out shed loads on their new "HD Ready" TV's to get fed up watching 1 channel of HD content and want more. Their only choice unfortunately will be to go to Sky HD.
I called Telewest last week to see if there was any word about when the current Sky HD content was coming to them and he said that all the current HD channels on Sky will be on cable by the end of Feb. This is clearly a sales pitch as I doubt for one second this is true.
It will be interesting to see what Virgin manage to do about this, or what they start broadcasting themselves, but we can't wait for ever until they stop arguing amongst themselves.