I would DEFINITELY NOT recommend this plugin for the following reasons.
1) The following is a quote from the developer's website ( http://www.prelovac.com/vladimir/wordpress-plugins/smart-youtube ):
Guys I am really sorry but I am not able to provide support for this plugin. That's the "price" of it being free. Most of the things you think don't work, really work, please check the documentation before you despair :)
2) Does not work on iPhone. I have had several complaints from clients and colleagues who are iPhone users & have tried to view my videos on websites. I have tried just about every setting I could think of in the plugin, but still cannot get it to work on iPhones.