So how many islands are there?

I've done a lot of research on the Great Barrier Reef and its islands. The Wikipedia claims there are 900, other places say just over 600. In a recent interview, Nicole McNaughton, PR Manager for the "Best Job in the World," mentioned 600. I am going with Nicole McNaughton :) However, I promise to investigate this mystery first-hand when I get there. I will take a picture of every island (might take a few years) and provide the proof!

PS. That's Dunk Island in the photo above.