Book it now since, as Alan B says, the price will go up. I have already booked my trip for July/August 2008.

But don't pick up the tickets yet. I am not aware of your travel situation but be aware that for the past several years they have had a promotion where kids travel free during the summer. Depending upon the number of kids, if any, you have, if the promotion is presented again you may be able to rebook for a lower fare.

Steve