Depends what you want to achieve.
Your virgin media technician MAY hook up to high quality coax if you pre-install it but the policy is they don't. Its not the same as distributing a standard RF signal, say from an aerial. The spec of the coax is totally different.
Personally if I were doing a rewire on a shell, I would be running CAT6 cabling thoughout as you can put pretty much any signal through it. Problem is knowing how many runs and to where. Ideally you want AT LEAST 2 runs per room back to a central point.
If you are certain you want to install Virgin Multiroom with several TiVo's, your best bet would be to run ducting the technicians can easily run the coax through.