I have noticed that my youtube button went missing...
After some messing around I have realised that the button is still actually there it's just the youtube icon that is missing, so there is now a blank space where it should be. Seems that after recently changing to AdBlock Plus (as an extension in my chrome browser) it had decided that the youtube icon is advertising and has removed it, my previous adblocker did not do this this.
Anyway, I thought I'd give you guys the heads-up just in case yours is doing this and you were wondering why you can't embed videos..