It's like a contemporary version of an ocean liner in some ways. Has lots of modern art and Celebrity staples such as Michael's Club cigar bar, Martini Bar, Aqua spa. She's 70,000 tons, has only a moderate amount of balconies, and is one of the more luxurious members of the Celebrity fleet.
The cruise line is definitely more formal and, almost, anti-Freestyle cruise. There are limited hours for almost everything. There's also no announcements, usually. Forget about casual dining, its by reservation only and quite limited.
Expect the usual types of activities on Celebrity, but not the extreme ones - and expect the ship to seem more laid back than NCL. With all of Celebrity's talk of innovation and technology in their ships they really are a fairly traditional cruise line.