I just tried the 3.6 Beta with twenty thirteen theme. I was excited about the audio video upload and tried to upload a video in mp4 format and published the post. Then went to live site and post did not appear on the site. I came back and clicked on "Post published view post" link and got a 404 page not found error. Then I came back and gave that post a title and updated it. It appeared on the site after that. I came back to post edit screen and removed post title and updated. The post title was not removed.
I don't know if it is a bug or not but it seems like I can't publish a video post without a title.