Embedding videos
Go to youtube, and find your video that you want to post. On the video's page, copy the URL (NOT the embed code, just the URL from your browser's address bar).
When you go to make a new post here, or edit an old one, there's a new button above the text entry box, called 'youtube.'
Click it. It will spit out something like this:
Paste the URL you copied earlier to the spot between the youtube tags, like so:
That's it! Simple.