Wow! This is a gorgeous ship. Its very elegant, refined but relaxed at the same time. Really, really clean, people cleaning all the time. The staff were nearly all outstanding (there's always one or two who aren't but not everyone can have a good day everyday).
The food in the MDR was good, ditto for the buffet. We ate in Qzine which was great, really inventively presented, amazing table right next to the window (nb if you aren't by the window you are sat very close to your neighbours if you only book a table for two).
I loved the little touches like the fact they wait for you at port with iced face towels for when you get back from your excursions etc. The entertainment around the ship was perfect, there was always something going on and if it wasn't to our taste we could just wander to another bar/lounge and find something that was. We always managed to find a nice seat somewhere.
Great cabin, light, spacious, amazing views over the wake of the ship.
Gorgeous, but go to Oia. Fira is nowhere near as nice. Oia is just stunning. We noticed that the celebrity excursions only gave you 40 minutes in Oia so you might want to know that at the port are lots of local small boats that will take you to Oia for 15 euros which includes the cost of a bus from Oia over to Fira. This way you save a lot of money plus you get to spend a couple of ours in Oia which is just stunning.
Really easy to just walk into Rhodes old town, which was lovely.
Stayed on ship