In no particular order, here are a few things to think about
* close to elevators/stairs?
* middle decks may have a hard time GETTING an elevator (on some ships anyway!) - if so, do you want to be closer to pools? dining room?
* What's above you (you probably don't want to be below a dining area, bar, or even pool area where the noise above is intrusive)
* Is window/balcony obstructed? (where are the lifeboats?)
... Just a few trivial thoughts on cabins selection
Sovereign of the Seas, 9/2003