Dana Howl has a great video up breaking down colour for miniature painters, pointing out why CMYK (used by printers) can by a better way of understanding colours and colour effects than red/yellow/blue and a colour wheel.
I know I will probably finish off my current collection of models using much the same painting techniques as I ever have, but videos like these are making me consider a fresh start with a fresh collection (within limits!) as being a potentially good thing.