A major advantage of RW is that it can be used in so many different ways. For anybody who can see my campaign preparations I'm obviously the queen of chaos, and therefore I use RW mainly to structure my thoughts and ideas. During play I just use it to show maps and pictures.

It might be best to imagine how this will work with per-character revelation.

While it is "all-or-nothing" at the moment, the intended functionality-to-come is for the reveal state to be per-character. Since the number of characters can vary widely from game to game, the best you could hope for is to show SOME, NONE, or ALL as reveal states.. and some would still require you to enter the topic to see which ones it is revealed to.

Maybe an empty, partially-filled, and wholly filled circle around the icon?

But then, that may be too busy. :(