There is an issue with uploading Youtube videos for some.
When tagging [youtube= and so on, when coming to a copy and paste from You Tube, ,many are saying the video is not appearing. I found a fix.
Do as you would always do when embedding a youtube video.
The only change is, when copying the Youtube link, paste it into a .Notepad first, then copy the URL from the Notepad into the tag [youtube= etc. it will 100% show the video.
I flagged the issue here: But found a workaround by change, A user last night had the same issue as you can see here The workaround helped her place the Youtube video also.

I hope this was typed in a way people understand how to work around the issue. It is not happening to everyone, but is to many