The ones recommended above are all terrific, with touringplans being my personal favorite for hardcore planning, because I'm an OCD overplanner, and touringplans allows me to research every detail to my heart's content. (I am a subscriber -- it's cheap -- so I have access to the full site.)
I use touringplans' Crowd Calendar to plan visit dates, and I use its Personalized Touring Plan feature to make plans for each day that include my dining reservations and FP+. I keep a Crowd Tracker going for my dates so I'm alerted to changes in crowd projections, hours and EMH. I can virtually check out the views from hotel rooms in my room category via the Resort Room Finder, and formulate a room request fax (which may or may not help, but why not?). I can get an up-to-date listing of closures and refurbishments that might affect my stay. I can research restaurants, view menus and even search for specific dishes using the Menu Search tool, and if there's a dining reservation I couldn't get the first time around, I can set up a Reservation Finder search that will alert me if the place/time I'm looking for becomes available (but then I have to click through as quickly as possible to score the reservation before someone else does). In the past, I've found touringplans' crowd and wait time projections to be pretty on point. My touringplans subscription (I also subscribe to its Universal and Disneyland planning services) has been, for me, a few dollars VERY well spent!
