Thanky!
We haven't figured out exactly how to surprise them yet. We want to keep it a surprise until the last possible moment, so we're just telling them we're going to the beach. When we're just a few miles out (Tam has been before, so she knows) we're going to tell them that we need to make a quick stop somewhere, but if they want to we can stay a bit longer. We are either going to wait until they figure it out on their own by what they see around them, or hand them a castle gift bag filled with disney themed goodies. Haven't quite decided yet.
They know we're planning a trip to DW in 09, so it's been easy to deflect all disney-mania on my part by saying I'm looking into it for our "two more summers" trip, as DD5 calls it.
Oooh, I can't wait to hear the shrieks of delight! It's going to be a long few weeks for me, trying to not leak the secret!