There is a lot of walking. Wear good broken in shoes. I had new Reeboks but had worn them for a month before the cruise. My friend had brand new shoes and got blisters. This ship is very nice, very clean.
We love Celebrity and really enjoy the menus. Be aware that you can order a shrimp cocktail every night for dinner and if you don't like the choices, you can get chicken breast, strip steak or salmon every noc.
Our waiter did not tell us this up front and one of our group is a very picky eater. He was happier with the alternative choices some nights. We also asked for a cheese and fruit tray every evening before ordering and sometimes used that as our appetizer. Don't be afraid to make any request. They will bend over backwards to make you happy.
I have reviewed this cruise on this site and will be happy to answer if you have any questions.