I booked my Category 1 in June 2001, for the cruise in March 2003.
Bear in mind that there are approximately 50 Magic cruises a year, two Disney Suites per cruise...that means only 100 families each year will be able to enjoy it. Add 200 more for the 3 and 4 day, and they go VERY quickly.
My advice?
I agree with the person who said "be flexible". That's the first thing.
The second thing is to understand that you'll have to book it almost 18 months out, so when you're near the time you want to cruise, call, EVERY day. Unfortunately, you may not get the same info twice, so call twice a day if it helps.
The cruise for my DW and three kids cost about $10,000. We love the extra space, the service and the perks. We usually low-key things at home, but LOVE to vacation "first class".
We can't wait!!!