The Caymans consist of Grand Cayman and the two smaller Little Cayman and Cayman Brac.
The latter 2 are 5 miles apart and they are away from the large island 89 miles away.
The temperature is averages at 27° c and the water temperature goes from 79° - 82° farenheight with a usual good visibility.
You can dive from shops or liveaboards.

 

The Caymans are well served by north american and european airlines as opposed to say Roatan in Honduras which is difficult to reach from Europe.
Cayman Airways is the national carrier and is diver friendly! That can be really attractive..

Getting to the Cayman Islands

British Airways fly there.
But it is well served from many U.S. cities especially Miami being 75 minutes away.

Things to Do

Outside of diving you can enjoy all the usual water sports like windsurfing or water skiing and more.
Also there is a submarine tour and above land you can play golf at one of the 3 courses. The range of accomodation are vast,
search here for some places to stay.

Some Stats

Size : 60 islands !
Population : 23,000
Main City : Road Town
Language : English
Currency :They use of the good ole USD $$$

Scuba Diving

The diving could not be more diverse from the well known stingray city
which is really shallow (perhaps a bit touristic and best snorkelled perhaps)
,to deep walls and wrecks. There is the common double wall drop off scenario where a shallower 60 foot-ish wall exists
for shallower diving but also the secondary dropoffs to as deep as you can go.
Brac has the MV Capt. Keith Tibbets a 330 foot Russian frigate - sunk in 1996. Also in Brac is Oceanic Voyagers ,
a 7 foot bronze sculpture created by Dale Evers, it's at Radar Reef. Little Caymens best wall is Bloody Bay Wall.

Tips and Tricks

Try the mudslide cocktails :) and try to see one of the few blue iguanas which can get to 1.5 m in length,look up Seven Mile Beach and the Botanic Park.

Some good websites on Scuba in Grand Cayman

http://beust.com/grand-cayman/