[salival]

I didn't forget about it and it is pretty usable, but (there's always a but) it is not optimal. I think there are too many letters onscreen at the same time, therefore it may appear cluttered. Because of all those characters on screen at the same time, they need to be smaller than they have to be. For some users with bad eyesight (to put it bluntly) this might cause difficulties.

In my view only the letters of the alphabet need to be on screen. Add a shift and capslock button to accomodate uppercase letters and a 'symbols' button for other characters. That way the characters can be larger which means it becomes more usable.