I'm going end of Nov thru the first week of Dec and I booked my room first as soon as I could (11 months out). Then I booked the airfare as soon as I could. Got a pretty good rate of $660 for the 4 of us out of Boston.
I have also booked my rental car at National for 8 days at $149 including all taxes and fees and now the rate is over $400!!

I think it's because I arrive the day after Thanksgiving though.
I have also already purchased the special event tickets to "Mickey's Very Merry Christmas Party".
I have also bought special Disney Christmas T-shirts that were on clearance at the
Disney Store for $4 for my 2 girls and my niece to wear down there.
I have also bought matching personalized shirts for my family to wear on MY 40th Birthday!!

Couldn't resist since they were on sale at www.disneydirect.com!
I have also already bought some Disney Dollars for spending money down there.
I still need to buy our Annual Passes and our Universal passes and book the PS in August/Sept.
I like doing everything I can early on. Sometimes you get a better rate that way too.