I really liked TGM. I agree with earlier posts about finding navigation diffiuclt, and I didn't get any e-mail updates for some reason.
The plans work a treat, and he gives lots of inside information. For example the best places to watch the fireworks at the parks, what to take with you to the park. Although my tip, is nothing other than your ticket and money.
I wouldn't leave it too long before your trip to join, as the more you use the website, the easier it gets.
Have fun.
There is also another wealth of info on touring plans at
WWW.touringplans.com
They also do a book with plans in, but it is very big and heavy reading material. In my view a lot is repeated. It lists scores for hotels, restuarants, rides. Gives advice on how to deal with difficult children, which I found strange that this needed to be included. Maybe American's need help in parenting children! I wouldn't have throught so. When we visited in the summer, I didn't see one misbehaved child.
The best book in my view for florida is a brits guide to orlando, but then I am from the UK!