Hey guys,

Thanks for the prompt reply!
I watched the gnomon tutorial on it and while he discusses the grading of the shot, he mentions another artist did it through Maya and will be speaking on it (but noone does! lol)
I checked out the link you posted aabout particles Displaced by Image Luminance and yeah - its sounds complicated but I don't mind looking in to it - particle systems that is. Otherwise, I can't think of any other way to approach this effect!

Ryan