For our last visit we bought
Attraction Tickets Direct 21 day ultimate tickets and reckoned they were the
best buy. Although we always use the park hopper part of the tickets we never need the water parks as we prefer the hotel pools and we don't use the Disney Quest tickets. We found that with the current exchange rate it was cheaper to buy for next year with mapleleaftickets.com as we only bought park hopper and not the add-ons, we saved about £200 for the four of us doing it this way. It does absolutely depend on what you want to do while you are there.
Also, we can buy tickets now for Feb 2009 from USA BUT UK tickets have to be used by end of 2008.