If you "Enable HTML Tags" by checking the box, below this text entry space, as you post to UtadaNet, YOU CAN HOTLINK YouTube Videos here. I have done it before. Here is an Example:

New Utada Kiss & Cry Music Video Pastiche or Mashup by and for her Fans

What you do, is you hit that little chain-like icon button up above size here in your message - first button - and you can enter the hotlink, and then your description of same. When you finish writing, and post your message here, the hotlink appears.