Here's the status of the bases.
Bermuda (not part of the original deal, but the US got basing rights there for free): Closed as a US base 1995.
Newfoundland (as Bermuda): The bases were closed 1961, 1966 and 1994. The land had been turned over to Canada 1975, but the US maintained a presence (a radar station) with Canadian permission.
Antigua: Closed 1949.
Bahamas: The base is closed, but Atlantic Undersea Test and Evaluation Center (AUTEC) retains a large testing lab on the island of Andros.
British Guyana: The base was closed 1949.
Jamaica: The base was closed 1949.
Santa Lucia: The base was closed 1949.
Trinidad: The base was closed 1949.
As you can see, most of these bases were closed shortly after the war. They had been created for naval recoinnasance over the central and south-central Atlantic as well as the Caribbean. The increasing range of radar systems and jet planes had made them mostly obselete by the end of the 1940s, and they were closed.
http://en.wikipedia.org/wiki/Destroyers_for_Bases_Agreement#The_bases
http://en.wikipedia.org/wiki/Atlantic_Undersea_Test_and_Evaluation_Center
Does anyone know why these leases, and the Hong Kong lease, are 99 years instead of 100?
Edit: wikipedia doesn't explain why it's's arbitrarily one year off a century.
Just curious, which islands are actually the ones rented?
Why did America want those bases anyway?
50 Destroyers seems quite a lot. Could someone give a short summary of the naval strength of the key players in WWII?