Determining the video url is done on pwnyoutube's server and they can set whatever referrer (or none) they like. The real question is whether Youtube will start checking the request ip address and block pwnyoutube's. But then just put the site in a cloud.
My experience is that Youtube combats this (either intentionally or just by way of code changes) by changing the method in which the flv urls are determined by the player. The download sites break until they reverse engineer, and the cycle continues.
considering youtube is starting to add their own download links (http://www.downloadsquad.com/2009/01/19/youtube-begins-addin...) and there are already tons of sites and utilities to download them already that haven't been blocked, i'd say youtube doesn't really care.
Those who want their sites/products to go mainstream without ridicule (ExpertSexChange.com/ExpertsExchange.com is a popular example) or false negative impression/bias. This is why people often spend a lot of time to choose a name carefully, especially when you consider the long-term branding and marketing.
this is something I've never understood about DRM. If I can watch/listen to it I can capture it. Period. DRM is supposed to simply make the barrier to piracy higher so that less people overall pirate.
But this is a total misunderstanding about how piracy works. Someone will take up the challenge of breaking your DRM, and when they do everyone will download it from that person and then each other. DRM is completely ineffective in a situation where a single point of failure means total failure.
