Better Code.

Matches:

youtube.com/v/vidid
youtube.com/vi/vidid
youtube.com/?v=vidid
youtube.com/?vi=vidid
youtube.com/watch?v=vidid
youtube.com/watch?vi=vidid
youtu.be/vidid
youtube.com/embed/vidid
http://youtube.com/v/vidid
http://www.youtube.com/v/vidid
https://www.youtube.com/v/vidid
youtube.com/watch?v=vidid&wtv=wtv
http://www.youtube.com/watch?dev=inprogress&v=vidid&feature=related
Does not match:

www.facebook.com?wtv=youtube.com/v/vidid