That's actually a script I threw together for my media server and happened to stumble upon this thread doing a search for updated Apple XML feeds.

Apple has broken things several times now which required some work-arounds over time. The 720p feed appears to recently become stale which I'll be post an updated version shortly to deal with this.

Here is where I post updated versions of the script:
http://majjix.com/luke/blog/081013/automatically-downloading-quicktime-trailers-and-posters