Hi Lyle,
What sort of building construction are we talking about here? (Timber framed or Brick)
At the very least, I'd install a good quality RG-6 coaxial cable and a Cat-5e or 6 cable to every point in the house where TV is most likely to be viewed.
Running these from a central point, say the attic, gives you a place to install any splitters, amplifiers and other equipment necessary to distribute the required signals.
Also, what type of services (eg.Terrestrial TV, Satellite, security cameras) will you be sending around the house?.
A big selling point here at least is pre-installed audio cabling for Home theatre.
But in any case, Lyle, I'd provide a few draw-wires in the walls, for future expansion later on, near the Main TV in the Lounge.
I've installed a lot of Home theatre wiring in existing houses over here and what I wouldn't have done for a draw-wire, considering that the top plate that you have to get to, is right over in the corner of the roof space.
Hope that this is of help. [Linked Image]