I have tested this on multiple installs and on a clean install of 3.3.1.
Automatic Posting of YouTube videos is being captcha blocked by YouTube. I have several multisite installs and all of my clients have YouTube videos that they upload regularly, which until the last month have automatically posted to their blogs without issue. This past month I received several complaints that their videos were no longer automatically posting. As I use a dedicated windows server I was able to login via remote desktop and when I try to visit YouTube via a browser I get a captcha that says too much activity is coming from our network.
I am confident that a workaround can be created and I have assigned one of my top coders to investigate this issue to search for a solution. However, until a solution can be identified it appears that Google/YouTube has shut down this plugin.
If anyone knows of a workaround for this I would love to hear it.