If your on Telstra and want a MASSIVE boost to your YouTube download speeds take the HTML5 beta.
All the videos then play using HTML5 rather than flash and the speed is insane. I can now download 1080p video much faster than it will play .... brilliant !
I'm assuming that YouTube must use different servers for the HTML5 content and Telstra hasn't limited downloading on these yet
I'm sure someone at Telstra will now spot this post and I will have ruined it for everybody but it's awesome while it lasts !!
Unfortunately flash based youtube is still absolutely pathetic on Telstra cable. I'm on 25M cable in Christchurch and I can download flash based youtube faster on my Telecom Blackberry setup as a modem than I can on 25M cable (when the XT network is working that is) .... Telstra still says, "There's nothing wrong" .... really REALLY annoys me!.
More information available here:
http://www.youtube.com/html5
Enjoy !