Got back from the Royalton Blue Waters in Montego Bay, and man, what a nice place. It was one of those perfect vacations that you only get 5-6 times in your life. It's all-inclusive and I highly recommend it.
It is a family resort, so keep that it in mind, however, there weren't a ton of kids. On site, there's water slides, a lazy river, and a few pools. However, it never felt that crowded. We never had a problem getting chairs at the pool or the beach even if we weren't down there first thing in the morning.
Restaurants at the resort (there were 6 or 7) were decent. Not super fine dining, but definitely good enough for an all-inclusive. Staff was excellent and attentive. Mixed drinks probably needed more alcohol, but Red Stripe was flowing like water so I didn't care.
Rooms were good, wifi was excellent throughout the resort (including the beach), and relaxation was paramount. Jamaican locals are super laid back, and very nice...to tourists anyway.
Excursions I recommend are the glowing lagoon, and Duns River Falls. There's also a coral reef off the coast so the snorkeling excursions are better than some of the places I've been.
Overall, stay around Montego Bay or Ocho Rios, and you'll be happy. Stay away from Kingston is what I heard.