First off, This only works with firefox. If you don't have it, download it, because this is by far the quickest and easiest way to convert youtube videos to mp4, FLV, or 3gp. So, Go to
https://addons.mozilla.org/en-US/firefox/addon/3006 and click "Download Now" When it comes up... hit okay and all that junk.. Then i believe it will ask you to set the folder for where you want your youtube videos to be kept. Set it to the same folder that you have set in the zune software for videos. Then go to youtube, and under the description box it should say download as mp4, FLV or 3gp. Click the mp4 link, because its the best for zune. The download box will come up, and the video should be in the zune software. Enjoy!
Mozzila Firefox download:
Oh yeah!! Does anyone know when new apps for the marketplace are scheduled to be released??
ZHD ROCKS