Everyone already knows about the Oasis. What it has, the size, the food, and so on. I experienced it all and it was great. I am working on a walkthrough video that took 45 minutes to see all the public areas; the ship is that big.
This boat makes you rethink cruising. We all thought about skipping a port because we've been there, I considered doing it so I could have the FlowRider (almost) to myself. This boat has something to offer everyone, and it is done so well that staying on the boat is a serious consideration from time to time.
Entertainment is nonstop. There are so many venues that there is something going on almost all the time. The daily schedules are so packed full that you get a additional page in your Compass (daily) for just evening activities. One example: Instead of just offering a great show like Hairspray, they also offer a dance class to learn the dances in the show. This is just one example, there are many more (and I'll be posting a full set of Compasses for the Eastern route).
This is the first cruise where I avoided the buffet entirely, and not because I chose to pay for breakfast or lunch. The Park Cafe is probably my single favorite place to eat on any cruise ship, breakfast sandwiches, bagel bar, lunch sandwiches (including the amazing roast beef sandwich), salad bar, deserts, and so on. All of it is good, and open until 6PM daily. I'm not knocking the buffet as I know it is popular and serves a purpose, but there are just so many other options for breakfast and lunch (Park Cafe and Wipeout Cafe to name some free ones).
The Royal Promenade is a feature that I think really sets many RCCL ships apart, and the Oasis continues that trend. On the Oasis it is so big that they can do Zumba classes in the morning, and on this ship the cruise director leads them. Central Park is 3 decks up and amazing in its own way. Quiet, home many specialty restaurants, and had softer live music in the evenings. I ate at Chops on the final day outside, and you would have thought you were on a quiet street in some city.
I was pleasantly surprised to see a very large number of non-US passengers on the boat. The Oasis must see a lot as many of the systems offered videos and text in more than 5 languages. Whereas many US cruisers don't (seem to) bring their kids to the specialty restaurants, those from outside the US frequently did. Something refreshing about seeing a 7 year old eat sushi, or a 6 year old eat at the "healthy" Solarium Bistro.
Despite being full, the boat had plenty of space. 5 pools and at least 6 hot tubs on deck 15 means that you could actually USE these, even during peak periods. The infinity hot tubs were rather nice, and since there were 2 big ones (divided into 2 sections each) there was always room. In addition, the 2 deck Serenity area was amazing, with 1 big round pool that had water jets and 2 hot tubs.
Only things I would change: Separate lines in Park Cafe for the salad/bagel bar and the sandwich area (if you've been, you'll agree), larger comedy club (every show booked full in advance, but you could usually get in due to no shows. Was told that it may be expanded during refurb), and add trash cans to the boardwalk. It would be nice to have lower prices on balconies during the summer (ouch!), but so long as the boat sails full there is no need.
The boat is so good that I had to change my spring break 2014 cruise (annual no-kid vacation for just the wife and I) to the sister ship Allure. It cost me a bit more, but to experience this type of vacation again I'll gladly pay it. I'm hoping that the Quantum can preserve this experience in a ship that holds ~33% fewer guests, I guess we will know in late 2014.