"haven't really" ??? well either you have or you haven't ? which is it?
if you HAVE, and googles' got you then you only have yourself to blame, all the "rules" are written... its all available, if you want to go black hat then be BLOODY good at it.
but to answer your question what to do:
content content UNIQUE content, stories stories stories, BLOGGGGGGGGG
this is what we are doing right now and seeing good success, sometimes feeding to facebook ( i don't have clients that can see benefits in twitter ) but bloging stories is working, i have a florist that blogs about sending flowers to a new mother with baby, i have a jewellery maker that blogs about what she created for a brides wedding etccc , google LOVES it.
its showing in their rankings and their stickiness
tim