Functional, but shoddy
I mean, lets be real, this is just a web wrapper around YouTube. Its sandboxed in a way that the YouTube player itself doesnt have permission to go fullscreen, even though the app can use the OS X fullscreen. The problem is that when its in OS X fullscreen, the window tries to disappear once it loses focus (i.e., you swipe to a different desktop/app), and then it gets really confused, leaving a black fullscreen app that you have to unfullscreen. You can use the settings to stop the disappearing act, but its clear that the app maker just pooped this out and is using as a vehicle to get you to buy their other apps too.
The app seems to eat the media button presses while its open, so they are basically dead keys.
Im using this as a glorified music playlist player and I dont care about the video at all. If I tried to use it as a proper YouTube interface, Id just uninstall it.
tiliv about GoVid for YouTube