Merritt:
The big HV distribution stuff is a little out of my league, but I do know that they also use a system similar to that which you described for the feeders to local xfmrs.
Yes - Residential service is normally just a 1-ph 2-w service with neutral and a hot leg at 240V to ground. In all but the odd remote property, residential services are just tapped off one phase of the standard 3-ph 4-w 240/415V wye.
Metering is just a simple 2-w meter although many people have the "Economy 7" tariff with a dual-reading meter for cheaper rates at night.
Most new services for all-electric homes are 100A, although 80A is still being installed for lower demand homes.
Older services are often lower: Many installed up until the late 1970s were 60A, and there are sill a few 40A (and even 30A) services on old houses that haven't been upgraded.
[This message has been edited by pauluk (edited 10-09-2001).]
