While methodologies have changed, and will continue to change,
SEO and what it should deliver has not. To me, that is being able to deliver what the client expects.
Biggest problems are... not being able to deliver, and not knowing what the client ultimately expects.
Personally what I'd like to see, is clients becoming more educated. This is where the good
SEO's will shine. They'll not only be "doing" they will be "educating". Separating themselves from all promises of "blue sky and sunshine" and simply being realistic. More of a symbiotic relationship.
Dave