"who were vacuumed up by NTL who were vacuumed up by Virgin Media who were vacuumed up by a faintly anonymous bunch (Global something or other - that the subscribers have probably never even heard of)."
Just as an FYI, NTL:Telewest bought the Virgin Media branding and then traded as Virgin Media while still being legally registered as NTL:Telewest. It was NTL:Telewest that sold out to Liberty Global.
You also missed the bit where Telewest "bought" NTL. (The reality was the opposite, but the legal fiction was created due to the Telewest contract with UKTV channels, which would be null and void in the event of Telewest begin bought out)