Is it in one of the recommended formats?
Supported YouTube formats - YouTube Help
I have not had any problems uploading videos that are less than 10 meg, but even those sometimes take an hour or more to get rendered by YouTube. They may be experiencing a large backlog or there is some kind of a connection problem. If the format is not correct or there is a problem with the video itself, that could be a show-stopper.
"Democracy is two wolves and a lamb voting on what to have for lunch. Liberty is a well-armed lamb contesting the vote." -- Benjamin Franklin