Ok to cut a long story short I've still got broadband and I'm still with Virgin Media.
After several emails and phone calls to both O2 and Virgin I eventually got through to a person in the disconnection department of Virgin. After they wanted to know why I was leaving they offered to better the deal offered by O2, but more importantly, they offered some advice on broadband speeds.
Well I checked out the speed that I could get by going through O2 (via BT line) which showed about 3 Meg and then checked out the speed I was getting at the moment via cable 9.4 Meg! Ok no contest. I did not realise that I would be dropping that amount of speed so Virgin won - sorry O2 when the speeds pick up I may reconsider but I use my broadband far too much to lose that amount of speed.
Oh well at least I learned a bit more about broadband.