We've not been on the Dream yet, but we have been on the Destiny, and the layouts are similar. We had cabin #6344 on the Destiny (L-shaped room) and loved it. The balcony is slightly wider, but the partition between it and cabin # 6346 is a fixed panel that cannot be opened. I believe the same is true for cabin #6490 & #6492 on the Dream. We'll be on the Liberty next May (2012), cabin #6450, and the layout on that ship is about the same as the Destiny and the Dream. This web site may be of help:
Your source for stateroom photographs | cruiselinerooms.com
Hope you have a great cruise!