Hi Catherine!
Now is as good a time as any to make reservations! Our family normally make December trips down to Disney, and secure our reservations generally as early as January or February. This gives the added advantage of setting a budget early, and putting a little to the side each month for the vacation trip. Last year, we stayed at the Animal Kingdom Lodge and got a Standard room with the Arusha Savannah view. We like the Arusha view because it appears to be the largest (Sunset and Uzima are the others), and the only savannah where you're guaranteed to see zebras. In addition to zebras, we saw ankole cattle, giraffes, ostrich, kudu, etc.
In terms of rates, keep an eye on Disney Special Offer rates, which you can access by clicking
here. Last year, we were able to take advantage of a 40% December discount by booking early. There's no guarantee they will offer the same special this year, but this is an example of what you may be able to take advantage of. Keep checking that link! :-)
Have a great time planning your Disney vacation!