Oldvarnish, I know of no dedicated blogs, but you can check out: Cruising to Calm
This is a blog called 'Cruising to Calm' and they spent considerable time in the area (from October 2008 to January 2009) and have many entries covering the islands off the coast of Venezuela
as well as Columbia
. In addition, you can always check out:
Numerous entries on security
in the area are available.
Finally, Chris Doyle now has a cruising guide to Venezuela
, as well as the island off the coast.
you can check out www.noonsite