We have cruised many times, mostly with Royal Caribbean.
We don't like spending much on board and can pretty much get by with all the complimentary options. We are a family with two relatively young kids (below 10).
We like to see places, but at the same time we also like a relaxed and laid-back holiday. A cruise helps us achieve this because our 'hotel' (i.e. the cruise ship) moves us from port to port. All the transfers from port to port would have killed us.
The Adventure Ocean program on Royal Caribbean serves us well too. Our kids spend many hours having a lot of fun, giving us precious couple time.
I have blogged about my cruises quite a bit. Most recent one is here:
http://guitar123foodandtravel.blogsp...ay-cruise.html