If I were pursuing this, I would look into how to make a plugin or an
extension (or at least find out the difference!). I wouldn't focus on
launchy.
For myself, right now I'm happy with all the options I have. In most cases
"HTML5 Video Everywhere!" is excellent. If I'm watching a screencast, I use
my hack. I made an alias to temptube called 'tt' so I just highlight the
URL, type tt in an open terminal, hit the middle-mouse-button to paste, then
hit Enter.
I still have to experiment with mps-youtube but it looks really cool--I love
cli applications.
