Ceres, all those things to update during rehearsal are great . . . but I have to admit, from both my personal experience, and watching other stage managers, once the computer is open and you start working on it DURING rehearsal, your attention is drawn to the laptop. And if your job is to keep the room moving, rehearsal going, and pay attention to everything happening in the room, the distraction of the open computer has proven to be a problem in my personal experience. Seriously, I have had actors stop acting until the SM stopped typing and throw a big fit about it. I have also seen directors just shut the laptop on a stage manager.
Yeah, it's a pain to stay after an hour, but . . . here's the thing. I have had assistants in the room for 8 hours, working away on paperwork, and when they look over the report at the end of the day, ask me . . . "When did we change that?", and I say, we worked that in rehearsal today, for about ten minutes, where were you? The answer is that they had their head in the paperwork, not in the rehearsal.
It's all about style, and there is also the issue of generational differences . . . work with older actors, directors, etc . . . they may not be part of the "computer" experience. I work with a director, who no matter what I am doing on the computer, they thing I am playing on the internet . . .
I also find, if I type notes as we work, I tend not to be as detailed as I like (I mean, I am split focus) and also, I tend to have to go back and edit a lot - because the note I type at the top of the rehearsal may be changed throughout the rehearsal.
Again, personal style, but I think it's a dangerous path to walk down. (Who hasn't started to type a note - and bingo, have an actor call for a line . . .)