I think it was a big help to us. I gave each person (kids included) a little chart that had blank space for each day we were there, divided into morning, afternoon, and evening. I asked people to list what they wanted to do or where they wanted to go.
We really didn't stick to that at all -- but what it DID do was give each of us an idea IN ADVANCE of what was important to the other people in our group. That way, when we were there, we weren't surprised when some of the people wanted to do different stuff than others of us did -- and they weren't surprised when we wanted to do something different than they did!
I'm a planner at heart -- with everything -- but don't get me wrong, I don't subscribe to the commando-style Disney World visit -- I prefer to just go with the flow and do what we feel like we want to do each day. HOWEVER, I will definitely do the same thing for our next trip -- it's just good to have an idea what you want to make sure you get to do, because the time goes by way too quick once you're there.
Just go, have fun, and enjoy!