I've gotten a little bit bored by the whole SEO thing.
SEO will eventually make you go mad, chasing that next thing....
Personally I think unless you have a huge budget and you can pay people to do MAJOR SEO work which shoots you to the top in a period of time you couldn't do unless you had BIG cash. I wouldn't bother.
Personally all I am doing now is :
Concentrating on building a good site
Creating interesting things people want to come and see/read.
Hopefully these people will then naturally link / tell other people about it.
Social Media Work in Line with the above
Making sure webmaster tools, sitemaps e.t.c are all up to date.
I was obsessed with PR, link building e.t.c. All your hard work could count for nothing after the next GOOGLE algorithm change. GOOGLE make you jump through hoops.
SEO is one way of getting traffic to your site, but not the only way and you shouldn't rely on that. That is why I just want a good site that hopefully and naturally climbs the google ladder whilst I am doing all the necessary other things I need to do which are getting the word out there
I LOATHE it and would happily pay a company (respectable one) to do it...
So in answer to your post content Marketing is just the next thing that will come along, you will put lots of hard work into and 6 months down the line changes. Google (I am Sure) are just trying to find the best sites out there, so just make the best site out there...