If you let people observe your game, will you be able to see how many are watching at the exact moment? I wont install the beta, cause it's too big and my internet sucks here, so i wouldn't know otherwise.
I don't think there is a way for players to see how many people are observing their games, but that would be a nice addition. If you have the game client open, you can see the number of observers in any particular game in the menu where you select which game you want to obs.