Cool, I wasn't expecting to see numbers forming as they filmed. Though I'm hoping it's something more mystical, I'm sure some will say they are just drones of some sort. Nonetheless, that's pretty cool to watch! :)
Edit: Just watched again and they're just planes (they said something about being mesmerized by the planes doing it or else...). I watched another video showing a close up of the planes/skywriters in Austin. I'm kinda bummed, lol