tahir - I remember now
Yes, that'll be fine - PM me when you've got dates in mind and I'll check the calendar.

anyhow, more chat... with the caveat that I'm more interested in DIY than a top-end bespoke commercial solution

Two things here:
1. designing an A/V system that works on day one.
2. minimising the impact when things change

Throwing lots of wire in and then thinking about it is a bad approach IMHO.
Designing a system and *then* throwing in lots more wire - that's better

I renovated but I ran 50mm waste pipe down from the attic to the ground floor; this is an option I'd look at very seriously.
Putting big drainpipes in every wall going up to the roof space would be very valuable.
Seriously: the other 'simple' solution is to build a bungalow or make sure there's a suspended floor
No worries with *anything* then; wiring, plumbing... simple.

Another of the big things that I think is missing here is that getting the distributed signal (ethernet) around the house isn't the hard part; it's getting from the point in the room where the signal comes out into the (mainly) analogue components.

The 'spec' includes squeezeboxes - but they need mains power, an amp (mains power and speaker-wire) and speakers (speaker wire). Getting the amplified sound to 2/4/5/7 locations around the room is a biggy.

Video goes via HDMI/DVI so you need a local video engine. Of course you could be lucky (or clever) and locate node0 to be local to everywhere.
OTOH with frontends shrinking all the time - and the fact that you'll want to plug in one or more of an Xbox, Xbox360, PS1, PS2, PS3, Wii (that covers the last 3 years right?) in one or more rooms - and I'd think of having a discrete breakout/node1 in an appropriate place in each room.