I would look into what it offers for kids. I'm sure it has tons, but all the "extra" stuff I hear about for the member cruise is lectures, tastings, etc that would obviously be geared more for adults. I'm betting since it's
DCL that they don't replace or take away any kids activities, but I'd just make sure the rest of the cruise is functioning as usual when taking kids. Does that make sense? I'm sure it's an easy answer to find. I just would imagine that if anything is 'missing' from the kids activity, AND it's a more expensive cruise, that another week - with better dates even - might be a better option. There are tons of DISers that always take the cruise though, so that would be really fun!
ETA: On second thought, book the WB Repo for 2010!