I know I'm probably late, but Jonathan M. Shiff is half reconsidering the fans demands on a new season. He's decided to make a spin-off of H2O instead, and this time, there will be a merman. Here's the link: http://if.com.au/2011/07/25/inprod/M...DSBAKTAGX.html

It's still in the development stage, but will probably air somewhere in 2012.