Hello to you both. I've just registered as a pro artist on the SAA site and have just picked up this issue. My main reputation is as a bird artist and I've developed a technique using a combination of airbrush and conventional paintbrush techniques. have a look at some of my work on http://www.birdingart.com/pages/thompson/carlthompson.html
I've found that the airbrush is fantastic at applying very fine transparent washes of colour, ideal for getting the lightness of feathers. I'll be demonstrating at the Wildlife Artist Society International annual exhibition at Nature in Art, Twigworth, Glouchester on 5th June. The Exhibition and ongoing demo is free. I'm also working on some instructional 'how to!' booklets for painting water, feathers, fur etc with an airbrush. Let me know if its something you would find interesting.