Jag,
When you put a lot of people on a non-switched LAN, which is what cable is from the neighborhood access points to the home, instead of DSL, which is fully switched, you got some issues.
Chief amongst them is that the local pr0n downloaders can affect your connection speed with their full-screen pictures.
DSL at the least, since it's fully switched (or claims to be), you should be able to pull some QoS on it at switch level and regulate connection speed to each port
. This means you can cap bandwidth usage and make for easier connection routing, therefore establishing lower ping times through intelligent establishment of connections.
If you know your switches, unlike Verizon apparently, you can pull off some tricks with DSL to route individual DSL connections by port, IP, or MAC address across the Internet using any routes you choose. Thus the advantages of switching. Cable doesn't have that, because it's not fully switched.
However, here in the USA, we have Verizon, who are just as brain-dead as Telstra, possibly more (and yes, it's probable). They're killing off the obviously better technology, and the cable companies are deploying the 5-minute solution to satiate the need for mp3s, pr0n, and gaming.
Source: Residential Broadband, by Cisco Systems. This book rocks and explains the difference between cable and DSL. What I got out of it is that when your neighbor is clicking on every Stile Project picture and movie and you have a cable modem, it affects you, whereas it does not when you have DSL.