In Release Notes I read: 
Notable fixes/changes in version 9.0c
    * Added.support for uploading high-definition content to YouTube.
    * Fixed a problem with importing audio from standard-definition DVD camcorder clips.
    * Fixed a bug that could cause Vegas Movie Studio to crash when using clips imported from DVD camcorders.
As I am much concerned with an easier way of HD upload to YT, I wanted to learn more about the update, but could find  it nowhere. Where to look for info?