Seems like this question is being brought up a lot, so I might as well explain it.
The main problem is how do we get a normal YouTube url like this
To embed a flash player on our post like this
http://www.youtube.com/v/ROvPB-V-39E
1.) Find your YouTube and copy the URL
2.) Start a post and click the Flash button, which looks like this:
3.) You'll see:
4.) Now take your Youtube url..
http://www.youtube.com/watch?v=ROvPB-V-39E
And change
watch?v= to just
/v/ like so it looks like this:
http://www.youtube.com/v/ROvPB-V-39E
5.) Insert the url that you made into the flash tags
[flash=200,200]http://www.youtube.com/v/ROvPB-V-39E[/flash]
And voila!
http://www.youtube.com/v/ROvPB-V-39EAs you may notice the dimensions of the video are a little weird. You can change the dimensions of the video with the height and width numbers in the flash tag.
[flash=WIDTH,HEIGHT]http://www.youtube.com/v/ROvPB-V-39E[/flash]
The numbers represent the amount of pixels.