We've been on 12 cruises now, all with RCL.. from the oldest ships (sovereign of the seas), and recently we were excited to check out Oasis of the seas, just to say to everyone else.. "we're sailing on the biggest cruise ship in the world!)..
We're going to stick with the slightly smaller ships in the future.. the Oasis class is designed to focus your attention on the inner-core of the ship, where there is a long "shopping mall"-ish promenade and very-nice actual tree-lined central park (you can even hear crickets chirping late at night), but since everything points inwards, there are no views of the ocean when you participate in any activity within the ship.
If you book, and you want to see the water, definitely book an ocean view room. Deck 4 is open to the water, but the lifeboats are blocking the entire view except for the back of the ship. At the top (where the pools are), you are over 15 stories high, so the water is so far down you feel like you're looking at it from the top of a condominium building..
Getting on the ship was very well organized
If you've been there, you know the deal.. if not, be prepared to be assaulted when you leave the ship.. If you're heading to paradise island (water park, casino, etc), there are plenty of group taxi's that will heard you up (for about $5 ea) and take you over.. don't expect a luxury ride ;) I WOULD NOT recommend just "winging-it" and walking around.. definitely book a shore excursion and stick with it, or just take a taxi to paradise island and stay there for the day, taxi's back to the ship are plentiful..